// +build sam,atsamd51 // Peripheral abstraction layer for the atsamd51. // // Datasheet: // http://ww1.microchip.com/downloads/en/DeviceDoc/60001507C.pdf // package machine import ( "device/arm" "device/sam" "errors" "runtime/interrupt" "runtime/volatile" "unsafe" ) func CPUFrequency() uint32 { return 120000000 } type PinMode uint8 const ( PinAnalog PinMode = 1 PinSERCOM PinMode = 2 PinSERCOMAlt PinMode = 3 PinTimer PinMode = 4 PinTimerAlt PinMode = 5 PinTCCPDEC PinMode = 6 PinCom PinMode = 7 PinSDHC PinMode = 8 PinI2S PinMode = 9 PinPCC PinMode = 10 PinGMAC PinMode = 11 PinACCLK PinMode = 12 PinCCL PinMode = 13 PinDigital PinMode = 14 PinInput PinMode = 15 PinInputPullup PinMode = 16 PinOutput PinMode = 17 PinPWME PinMode = PinTimer PinPWMF PinMode = PinTimerAlt PinPWMG PinMode = PinTCCPDEC PinInputPulldown PinMode = 18 ) type PinChange uint8 // Pin change interrupt constants for SetInterrupt. const ( PinRising PinChange = sam.EIC_CONFIG_SENSE0_RISE PinFalling PinChange = sam.EIC_CONFIG_SENSE0_FALL PinToggle PinChange = sam.EIC_CONFIG_SENSE0_BOTH ) // Callbacks to be called for pins configured with SetInterrupt. Unfortunately, // we also need to keep track of which interrupt channel is used by which pin, // as the only alternative would be iterating through all pins. // // We're using the magic constant 16 here because the SAM D21 has 16 interrupt // channels configurable for pins. var ( interruptPins [16]Pin // warning: the value is invalid when pinCallbacks[i] is not set! pinCallbacks [16]func(Pin) ) // Hardware pins const ( PA00 Pin = 0 PA01 Pin = 1 PA02 Pin = 2 PA03 Pin = 3 PA04 Pin = 4 PA05 Pin = 5 PA06 Pin = 6 PA07 Pin = 7 PA08 Pin = 8 PA09 Pin = 9 PA10 Pin = 10 PA11 Pin = 11 PA12 Pin = 12 PA13 Pin = 13 PA14 Pin = 14 PA15 Pin = 15 PA16 Pin = 16 PA17 Pin = 17 PA18 Pin = 18 PA19 Pin = 19 PA20 Pin = 20 PA21 Pin = 21 PA22 Pin = 22 PA23 Pin = 23 PA24 Pin = 24 PA25 Pin = 25 PA26 Pin = 26 PA27 Pin = 27 PA28 Pin = 28 PA29 Pin = 29 PA30 Pin = 30 PA31 Pin = 31 PB00 Pin = 32 PB01 Pin = 33 PB02 Pin = 34 PB03 Pin = 35 PB04 Pin = 36 PB05 Pin = 37 PB06 Pin = 38 PB07 Pin = 39 PB08 Pin = 40 PB09 Pin = 41 PB10 Pin = 42 PB11 Pin = 43 PB12 Pin = 44 PB13 Pin = 45 PB14 Pin = 46 PB15 Pin = 47 PB16 Pin = 48 PB17 Pin = 49 PB18 Pin = 50 PB19 Pin = 51 PB20 Pin = 52 PB21 Pin = 53 PB22 Pin = 54 PB23 Pin = 55 PB24 Pin = 56 PB25 Pin = 57 PB26 Pin = 58 PB27 Pin = 59 PB28 Pin = 60 PB29 Pin = 61 PB30 Pin = 62 PB31 Pin = 63 PC00 Pin = 64 PC01 Pin = 65 PC02 Pin = 66 PC03 Pin = 67 PC04 Pin = 68 PC05 Pin = 69 PC06 Pin = 70 PC07 Pin = 71 PC08 Pin = 72 PC09 Pin = 73 PC10 Pin = 74 PC11 Pin = 75 PC12 Pin = 76 PC13 Pin = 77 PC14 Pin = 78 PC15 Pin = 79 PC16 Pin = 80 PC17 Pin = 81 PC18 Pin = 82 PC19 Pin = 83 PC20 Pin = 84 PC21 Pin = 85 PC22 Pin = 86 PC23 Pin = 87 PC24 Pin = 88 PC25 Pin = 89 PC26 Pin = 90 PC27 Pin = 91 PC28 Pin = 92 PC29 Pin = 93 PC30 Pin = 94 PC31 Pin = 95 PD00 Pin = 96 PD01 Pin = 97 PD02 Pin = 98 PD03 Pin = 99 PD04 Pin = 100 PD05 Pin = 101 PD06 Pin = 102 PD07 Pin = 103 PD08 Pin = 104 PD09 Pin = 105 PD10 Pin = 106 PD11 Pin = 107 PD12 Pin = 108 PD13 Pin = 109 PD14 Pin = 110 PD15 Pin = 111 PD16 Pin = 112 PD17 Pin = 113 PD18 Pin = 114 PD19 Pin = 115 PD20 Pin = 116 PD21 Pin = 117 PD22 Pin = 118 PD23 Pin = 119 PD24 Pin = 120 PD25 Pin = 121 PD26 Pin = 122 PD27 Pin = 123 PD28 Pin = 124 PD29 Pin = 125 PD30 Pin = 126 PD31 Pin = 127 ) const ( pinPadMapSERCOM0Pad0 uint16 = 0x1000 pinPadMapSERCOM1Pad0 uint16 = 0x2000 pinPadMapSERCOM2Pad0 uint16 = 0x3000 pinPadMapSERCOM3Pad0 uint16 = 0x4000 pinPadMapSERCOM4Pad0 uint16 = 0x5000 pinPadMapSERCOM5Pad0 uint16 = 0x6000 pinPadMapSERCOM6Pad0 uint16 = 0x7000 pinPadMapSERCOM7Pad0 uint16 = 0x8000 pinPadMapSERCOM0Pad2 uint16 = 0x1200 pinPadMapSERCOM1Pad2 uint16 = 0x2200 pinPadMapSERCOM2Pad2 uint16 = 0x3200 pinPadMapSERCOM3Pad2 uint16 = 0x4200 pinPadMapSERCOM4Pad2 uint16 = 0x5200 pinPadMapSERCOM5Pad2 uint16 = 0x6200 pinPadMapSERCOM6Pad2 uint16 = 0x7200 pinPadMapSERCOM7Pad2 uint16 = 0x8200 pinPadMapSERCOM0AltPad0 uint16 = 0x0010 pinPadMapSERCOM1AltPad0 uint16 = 0x0020 pinPadMapSERCOM2AltPad0 uint16 = 0x0030 pinPadMapSERCOM3AltPad0 uint16 = 0x0040 pinPadMapSERCOM4AltPad0 uint16 = 0x0050 pinPadMapSERCOM5AltPad0 uint16 = 0x0060 pinPadMapSERCOM6AltPad0 uint16 = 0x0070 pinPadMapSERCOM7AltPad0 uint16 = 0x0080 pinPadMapSERCOM0AltPad1 uint16 = 0x0011 pinPadMapSERCOM1AltPad1 uint16 = 0x0021 pinPadMapSERCOM2AltPad1 uint16 = 0x0031 pinPadMapSERCOM3AltPad1 uint16 = 0x0041 pinPadMapSERCOM4AltPad1 uint16 = 0x0051 pinPadMapSERCOM5AltPad1 uint16 = 0x0061 pinPadMapSERCOM6AltPad1 uint16 = 0x0071 pinPadMapSERCOM7AltPad1 uint16 = 0x0081 pinPadMapSERCOM0AltPad2 uint16 = 0x0012 pinPadMapSERCOM1AltPad2 uint16 = 0x0022 pinPadMapSERCOM2AltPad2 uint16 = 0x0032 pinPadMapSERCOM3AltPad2 uint16 = 0x0042 pinPadMapSERCOM4AltPad2 uint16 = 0x0052 pinPadMapSERCOM5AltPad2 uint16 = 0x0062 pinPadMapSERCOM6AltPad2 uint16 = 0x0072 pinPadMapSERCOM7AltPad2 uint16 = 0x0082 ) // pinPadMapping lists which pins have which SERCOMs attached to them. // The encoding is rather dense, with each uint16 encoding two pins and both // SERCOM and SERCOM-ALT. // // Observations: // * There are eight SERCOMs. Those SERCOM numbers can be encoded in 4 bits. // * Even pad numbers are usually on even pins, and odd pad numbers are usually // on odd pins. The exception is SERCOM-ALT, which sometimes swaps pad 0 and 1. // With that, there is still an invariant that the pad number for an odd pin is // the pad number for the corresponding even pin with the low bit toggled. // * Pin pads come in pairs. If PA00 has pad 0, then PA01 has pad 1. // With this information, we can encode SERCOM pin/pad numbers much more // efficiently. Due to pads coming in pairs, we can ignore half the pins: the // information for an odd pin can be calculated easily from the preceding even // pin. // // Each word below is split in two bytes. The 8 high bytes are for SERCOM and // the 8 low bits are for SERCOM-ALT. Of each byte, the 4 high bits encode the // SERCOM + 1 while the two low bits encodes the pad number (the pad number for // the odd pin can be trivially calculated by toggling the low bit of the pad // number). It encodes SERCOM + 1 instead of just the SERCOM number, to make it // easy to check whether a nibble is set at all. // // Datasheet: http://ww1.microchip.com/downloads/en/DeviceDoc/60001507E.pdf var pinPadMapping = [64]uint16{ // page 32 PA00 / 2: 0 | pinPadMapSERCOM1AltPad0, // page 33 PB08 / 2: 0 | pinPadMapSERCOM4AltPad0, PA04 / 2: 0 | pinPadMapSERCOM0AltPad0, PA06 / 2: 0 | pinPadMapSERCOM0AltPad2, PC04 / 2: pinPadMapSERCOM6Pad0 | 0, PC06 / 2: pinPadMapSERCOM6Pad2 | 0, PA08 / 2: pinPadMapSERCOM0Pad0 | pinPadMapSERCOM2AltPad1, PA10 / 2: pinPadMapSERCOM0Pad2 | pinPadMapSERCOM2AltPad2, PB10 / 2: 0 | pinPadMapSERCOM4AltPad2, PB12 / 2: pinPadMapSERCOM4Pad0 | 0, PB14 / 2: pinPadMapSERCOM4Pad2 | 0, PD08 / 2: pinPadMapSERCOM7Pad0 | pinPadMapSERCOM6AltPad1, PD10 / 2: pinPadMapSERCOM7Pad2 | pinPadMapSERCOM6AltPad2, PC10 / 2: pinPadMapSERCOM6Pad2 | pinPadMapSERCOM7AltPad2, // page 34 PC12 / 2: pinPadMapSERCOM7Pad0 | pinPadMapSERCOM6AltPad1, PC14 / 2: pinPadMapSERCOM7Pad2 | pinPadMapSERCOM6AltPad2, PA12 / 2: pinPadMapSERCOM2Pad0 | pinPadMapSERCOM4AltPad1, PA14 / 2: pinPadMapSERCOM2Pad2 | pinPadMapSERCOM4AltPad2, PA16 / 2: pinPadMapSERCOM1Pad0 | pinPadMapSERCOM3AltPad1, PA18 / 2: pinPadMapSERCOM1Pad2 | pinPadMapSERCOM3AltPad2, PC16 / 2: pinPadMapSERCOM6Pad0 | pinPadMapSERCOM0AltPad1, PC18 / 2: pinPadMapSERCOM6Pad2 | pinPadMapSERCOM0AltPad2, PC22 / 2: pinPadMapSERCOM1Pad0 | pinPadMapSERCOM3AltPad1, PD20 / 2: pinPadMapSERCOM1Pad2 | pinPadMapSERCOM3AltPad2, PB16 / 2: pinPadMapSERCOM5Pad0 | 0, PB18 / 2: pinPadMapSERCOM5Pad2 | pinPadMapSERCOM7AltPad2, // page 35 PB20 / 2: pinPadMapSERCOM3Pad0 | pinPadMapSERCOM7AltPad1, PA20 / 2: pinPadMapSERCOM5Pad2 | pinPadMapSERCOM3AltPad2, PA22 / 2: pinPadMapSERCOM3Pad0 | pinPadMapSERCOM5AltPad1, PA24 / 2: pinPadMapSERCOM3Pad2 | pinPadMapSERCOM5AltPad2, PB22 / 2: pinPadMapSERCOM1Pad2 | pinPadMapSERCOM5AltPad2, PB24 / 2: pinPadMapSERCOM0Pad0 | pinPadMapSERCOM2AltPad1, PB26 / 2: pinPadMapSERCOM2Pad0 | pinPadMapSERCOM4AltPad1, PB28 / 2: pinPadMapSERCOM2Pad2 | pinPadMapSERCOM4AltPad2, PC24 / 2: pinPadMapSERCOM0Pad2 | pinPadMapSERCOM2AltPad2, //PC26 / 2: pinPadMapSERCOM1Pad1 | 0, // note: PC26 doesn't support SERCOM, but PC27 does //PC28 / 2: pinPadMapSERCOM1Pad1 | 0, // note: PC29 doesn't exist in the datasheet? PA30 / 2: 0 | pinPadMapSERCOM1AltPad2, // page 36 PB30 / 2: 0 | pinPadMapSERCOM5AltPad1, PB00 / 2: 0 | pinPadMapSERCOM5AltPad2, PB02 / 2: 0 | pinPadMapSERCOM5AltPad0, } // findPinPadMapping looks up the pad number and the pinmode for a given pin and // SERCOM number. The result can either be SERCOM, SERCOM-ALT, or "not found" // (indicated by returning ok=false). The pad number is returned to calculate // the DOPO/DIPO bitfields of the various serial peripherals. func findPinPadMapping(sercom uint8, pin Pin) (pinMode PinMode, pad uint32, ok bool) { if int(pin)/2 >= len(pinPadMapping) { // This is probably NoPin, for which no mapping is available. return } bytes := pinPadMapping[pin/2] upper := byte(bytes >> 8) lower := byte(bytes & 0xff) if upper != 0 { // SERCOM if (upper>>4)-1 == sercom { pinMode = PinSERCOM pad |= uint32(upper % 4) ok = true } } if lower != 0 { // SERCOM-ALT if (lower>>4)-1 == sercom { pinMode = PinSERCOMAlt pad |= uint32(lower % 4) ok = true } } if ok { // If the pin is uneven, toggle the lowest bit of the pad number. if pin&1 != 0 { pad ^= 1 } } return } // SetInterrupt sets an interrupt to be executed when a particular pin changes // state. The pin should already be configured as an input, including a pull up // or down if no external pull is provided. // // This call will replace a previously set callback on this pin. You can pass a // nil func to unset the pin change interrupt. If you do so, the change // parameter is ignored and can be set to any value (such as 0). func (p Pin) SetInterrupt(change PinChange, callback func(Pin)) error { // Most pins follow a common pattern where the EXTINT value is the pin // number modulo 16. However, there are a few exceptions, as you can see // below. extint := uint8(0) switch p { case PA08: // Connected to NMI. This is not currently supported. return ErrInvalidInputPin case PB26: extint = 12 case PB27: extint = 13 case PB28: extint = 14 case PB29: extint = 15 case PC07: extint = 9 case PD08: extint = 3 case PD09: extint = 4 case PD10: extint = 5 case PD11: extint = 6 case PD12: extint = 7 case PD20: extint = 10 case PD21: extint = 11 default: // All other pins follow a normal pattern. extint = uint8(p) % 16 } if callback == nil { // Disable this pin interrupt (if it was enabled). sam.EIC.INTENCLR.Set(1 << extint) if pinCallbacks[extint] != nil { pinCallbacks[extint] = nil } return nil } if pinCallbacks[extint] != nil { // The pin was already configured. // To properly re-configure a pin, unset it first and set a new // configuration. return ErrNoPinChangeChannel } pinCallbacks[extint] = callback interruptPins[extint] = p if !sam.EIC.CTRLA.HasBits(sam.EIC_CTRLA_ENABLE) { // EIC peripheral has not yet been initialized. Initialize it now. // The EIC needs two clocks: CLK_EIC_APB and GCLK_EIC. CLK_EIC_APB is // enabled by default, so doesn't have to be re-enabled. The other is // required for detecting edges and must be enabled manually. sam.GCLK.PCHCTRL[4].Set((sam.GCLK_PCHCTRL_GEN_GCLK0 << sam.GCLK_PCHCTRL_GEN_Pos) | sam.GCLK_PCHCTRL_CHEN) // should not be necessary (CLKCTRL is not synchronized) for sam.GCLK.SYNCBUSY.HasBits(sam.GCLK_SYNCBUSY_GENCTRL_GCLK0 << sam.GCLK_SYNCBUSY_GENCTRL_Pos) { } } // CONFIG register is enable-protected, so disable EIC. sam.EIC.CTRLA.ClearBits(sam.EIC_CTRLA_ENABLE) // Configure this pin. Set the 4 bits of the EIC.CONFIGx register to the // sense value (filter bit set to 0, sense bits set to the change value). addr := &sam.EIC.CONFIG[0] if extint >= 8 { addr = &sam.EIC.CONFIG[1] } pos := (extint % 8) * 4 // bit position in register addr.ReplaceBits(uint32(change), 0xf, pos) // Enable external interrupt for this pin. sam.EIC.INTENSET.Set(1 << extint) sam.EIC.CTRLA.Set(sam.EIC_CTRLA_ENABLE) for sam.EIC.SYNCBUSY.HasBits(sam.EIC_SYNCBUSY_ENABLE) { } // Set the PMUXEN flag, while keeping the INEN and PULLEN flags (if they // were set before). This avoids clearing the pin pull mode while // configuring the pin interrupt. p.setPinCfg(sam.PORT_GROUP_PINCFG_PMUXEN | (p.getPinCfg() & (sam.PORT_GROUP_PINCFG_INEN | sam.PORT_GROUP_PINCFG_PULLEN))) if p&1 > 0 { // odd pin, so save the even pins val := p.getPMux() & sam.PORT_GROUP_PMUX_PMUXE_Msk p.setPMux(val | (0 << sam.PORT_GROUP_PMUX_PMUXO_Pos)) } else { // even pin, so save the odd pins val := p.getPMux() & sam.PORT_GROUP_PMUX_PMUXO_Msk p.setPMux(val | (0 << sam.PORT_GROUP_PMUX_PMUXE_Pos)) } handleEICInterrupt := func(interrupt.Interrupt) { flags := sam.EIC.INTFLAG.Get() sam.EIC.INTFLAG.Set(flags) // clear interrupt for i := uint(0); i < 16; i++ { // there are 16 channels if flags&(1<>pin_in_group)&1 > 0 } // Toggle switches an output pin from low to high or from high to low. // Warning: only use this on an output pin! func (p Pin) Toggle() { group, pin_in_group := p.getPinGrouping() sam.PORT.GROUP[group].OUTTGL.Set(1 << pin_in_group) } // Configure this pin with the given configuration. func (p Pin) Configure(config PinConfig) { group, pin_in_group := p.getPinGrouping() switch config.Mode { case PinOutput: sam.PORT.GROUP[group].DIRSET.Set(1 << pin_in_group) // output is also set to input enable so pin can read back its own value p.setPinCfg(sam.PORT_GROUP_PINCFG_INEN) case PinInput: sam.PORT.GROUP[group].DIRCLR.Set(1 << pin_in_group) p.setPinCfg(sam.PORT_GROUP_PINCFG_INEN) case PinInputPulldown: sam.PORT.GROUP[group].DIRCLR.Set(1 << pin_in_group) sam.PORT.GROUP[group].OUTCLR.Set(1 << pin_in_group) p.setPinCfg(sam.PORT_GROUP_PINCFG_INEN | sam.PORT_GROUP_PINCFG_PULLEN) case PinInputPullup: sam.PORT.GROUP[group].DIRCLR.Set(1 << pin_in_group) sam.PORT.GROUP[group].OUTSET.Set(1 << pin_in_group) p.setPinCfg(sam.PORT_GROUP_PINCFG_INEN | sam.PORT_GROUP_PINCFG_PULLEN) case PinSERCOM: if p&1 > 0 { // odd pin, so save the even pins val := p.getPMux() & sam.PORT_GROUP_PMUX_PMUXE_Msk p.setPMux(val | (uint8(PinSERCOM) << sam.PORT_GROUP_PMUX_PMUXO_Pos)) } else { // even pin, so save the odd pins val := p.getPMux() & sam.PORT_GROUP_PMUX_PMUXO_Msk p.setPMux(val | (uint8(PinSERCOM) << sam.PORT_GROUP_PMUX_PMUXE_Pos)) } // enable port config p.setPinCfg(sam.PORT_GROUP_PINCFG_PMUXEN | sam.PORT_GROUP_PINCFG_DRVSTR | sam.PORT_GROUP_PINCFG_INEN) case PinSERCOMAlt: if p&1 > 0 { // odd pin, so save the even pins val := p.getPMux() & sam.PORT_GROUP_PMUX_PMUXE_Msk p.setPMux(val | (uint8(PinSERCOMAlt) << sam.PORT_GROUP_PMUX_PMUXO_Pos)) } else { // even pin, so save the odd pins val := p.getPMux() & sam.PORT_GROUP_PMUX_PMUXO_Msk p.setPMux(val | (uint8(PinSERCOMAlt) << sam.PORT_GROUP_PMUX_PMUXE_Pos)) } // enable port config p.setPinCfg(sam.PORT_GROUP_PINCFG_PMUXEN | sam.PORT_GROUP_PINCFG_DRVSTR) case PinCom: if p&1 > 0 { // odd pin, so save the even pins val := p.getPMux() & sam.PORT_GROUP_PMUX_PMUXE_Msk p.setPMux(val | (uint8(PinCom) << sam.PORT_GROUP_PMUX_PMUXO_Pos)) } else { // even pin, so save the odd pins val := p.getPMux() & sam.PORT_GROUP_PMUX_PMUXO_Msk p.setPMux(val | (uint8(PinCom) << sam.PORT_GROUP_PMUX_PMUXE_Pos)) } // enable port config p.setPinCfg(sam.PORT_GROUP_PINCFG_PMUXEN) case PinAnalog: if p&1 > 0 { // odd pin, so save the even pins val := p.getPMux() & sam.PORT_GROUP_PMUX_PMUXE_Msk p.setPMux(val | (uint8(PinAnalog) << sam.PORT_GROUP_PMUX_PMUXO_Pos)) } else { // even pin, so save the odd pins val := p.getPMux() & sam.PORT_GROUP_PMUX_PMUXO_Msk p.setPMux(val | (uint8(PinAnalog) << sam.PORT_GROUP_PMUX_PMUXE_Pos)) } // enable port config p.setPinCfg(sam.PORT_GROUP_PINCFG_PMUXEN | sam.PORT_GROUP_PINCFG_DRVSTR) } } // getPMux returns the value for the correct PMUX register for this pin. func (p Pin) getPMux() uint8 { group, pin_in_group := p.getPinGrouping() return sam.PORT.GROUP[group].PMUX[pin_in_group>>1].Get() } // setPMux sets the value for the correct PMUX register for this pin. func (p Pin) setPMux(val uint8) { group, pin_in_group := p.getPinGrouping() sam.PORT.GROUP[group].PMUX[pin_in_group>>1].Set(val) } // getPinCfg returns the value for the correct PINCFG register for this pin. func (p Pin) getPinCfg() uint8 { group, pin_in_group := p.getPinGrouping() return sam.PORT.GROUP[group].PINCFG[pin_in_group].Get() } // setPinCfg sets the value for the correct PINCFG register for this pin. func (p Pin) setPinCfg(val uint8) { group, pin_in_group := p.getPinGrouping() sam.PORT.GROUP[group].PINCFG[pin_in_group].Set(val) } // getPinGrouping calculates the gpio group and pin id from the pin number. // Pins are split into groups of 32, and each group has its own set of // control registers. func (p Pin) getPinGrouping() (uint8, uint8) { group := uint8(p) >> 5 pin_in_group := uint8(p) & 0x1f return group, pin_in_group } // InitADC initializes the ADC. func InitADC() { // ADC Bias Calibration // NVMCTRL_SW0 0x00800080 // #define ADC0_FUSES_BIASCOMP_ADDR NVMCTRL_SW0 // #define ADC0_FUSES_BIASCOMP_Pos 2 /**< \brief (NVMCTRL_SW0) ADC Comparator Scaling */ // #define ADC0_FUSES_BIASCOMP_Msk (_Ul(0x7) << ADC0_FUSES_BIASCOMP_Pos) // #define ADC0_FUSES_BIASCOMP(value) (ADC0_FUSES_BIASCOMP_Msk & ((value) << ADC0_FUSES_BIASCOMP_Pos)) // #define ADC0_FUSES_BIASR2R_ADDR NVMCTRL_SW0 // #define ADC0_FUSES_BIASR2R_Pos 8 /**< \brief (NVMCTRL_SW0) ADC Bias R2R ampli scaling */ // #define ADC0_FUSES_BIASR2R_Msk (_Ul(0x7) << ADC0_FUSES_BIASR2R_Pos) // #define ADC0_FUSES_BIASR2R(value) (ADC0_FUSES_BIASR2R_Msk & ((value) << ADC0_FUSES_BIASR2R_Pos)) // #define ADC0_FUSES_BIASREFBUF_ADDR NVMCTRL_SW0 // #define ADC0_FUSES_BIASREFBUF_Pos 5 /**< \brief (NVMCTRL_SW0) ADC Bias Reference Buffer Scaling */ // #define ADC0_FUSES_BIASREFBUF_Msk (_Ul(0x7) << ADC0_FUSES_BIASREFBUF_Pos) // #define ADC0_FUSES_BIASREFBUF(value) (ADC0_FUSES_BIASREFBUF_Msk & ((value) << ADC0_FUSES_BIASREFBUF_Pos)) // #define ADC1_FUSES_BIASCOMP_ADDR NVMCTRL_SW0 // #define ADC1_FUSES_BIASCOMP_Pos 16 /**< \brief (NVMCTRL_SW0) ADC Comparator Scaling */ // #define ADC1_FUSES_BIASCOMP_Msk (_Ul(0x7) << ADC1_FUSES_BIASCOMP_Pos) // #define ADC1_FUSES_BIASCOMP(value) (ADC1_FUSES_BIASCOMP_Msk & ((value) << ADC1_FUSES_BIASCOMP_Pos)) // #define ADC1_FUSES_BIASR2R_ADDR NVMCTRL_SW0 // #define ADC1_FUSES_BIASR2R_Pos 22 /**< \brief (NVMCTRL_SW0) ADC Bias R2R ampli scaling */ // #define ADC1_FUSES_BIASR2R_Msk (_Ul(0x7) << ADC1_FUSES_BIASR2R_Pos) // #define ADC1_FUSES_BIASR2R(value) (ADC1_FUSES_BIASR2R_Msk & ((value) << ADC1_FUSES_BIASR2R_Pos)) // #define ADC1_FUSES_BIASREFBUF_ADDR NVMCTRL_SW0 // #define ADC1_FUSES_BIASREFBUF_Pos 19 /**< \brief (NVMCTRL_SW0) ADC Bias Reference Buffer Scaling */ // #define ADC1_FUSES_BIASREFBUF_Msk (_Ul(0x7) << ADC1_FUSES_BIASREFBUF_Pos) // #define ADC1_FUSES_BIASREFBUF(value) (ADC1_FUSES_BIASREFBUF_Msk & ((value) << ADC1_FUSES_BIASREFBUF_Pos)) adcFuse := *(*uint32)(unsafe.Pointer(uintptr(0x00800080))) // uint32_t biascomp = (*((uint32_t *)ADC0_FUSES_BIASCOMP_ADDR) & ADC0_FUSES_BIASCOMP_Msk) >> ADC0_FUSES_BIASCOMP_Pos; biascomp := (adcFuse & uint32(0x7<<2)) //>> 2 // uint32_t biasr2r = (*((uint32_t *)ADC0_FUSES_BIASR2R_ADDR) & ADC0_FUSES_BIASR2R_Msk) >> ADC0_FUSES_BIASR2R_Pos; biasr2r := (adcFuse & uint32(0x7<<8)) //>> 8 // uint32_t biasref = (*((uint32_t *)ADC0_FUSES_BIASREFBUF_ADDR) & ADC0_FUSES_BIASREFBUF_Msk) >> ADC0_FUSES_BIASREFBUF_Pos; biasref := (adcFuse & uint32(0x7<<5)) //>> 5 // calibrate ADC0 sam.ADC0.CALIB.Set(uint16(biascomp | biasr2r | biasref)) // biascomp = (*((uint32_t *)ADC1_FUSES_BIASCOMP_ADDR) & ADC1_FUSES_BIASCOMP_Msk) >> ADC1_FUSES_BIASCOMP_Pos; biascomp = (adcFuse & uint32(0x7<<16)) //>> 16 // biasr2r = (*((uint32_t *)ADC1_FUSES_BIASR2R_ADDR) & ADC1_FUSES_BIASR2R_Msk) >> ADC1_FUSES_BIASR2R_Pos; biasr2r = (adcFuse & uint32(0x7<<22)) //>> 22 // biasref = (*((uint32_t *)ADC1_FUSES_BIASREFBUF_ADDR) & ADC1_FUSES_BIASREFBUF_Msk) >> ADC1_FUSES_BIASREFBUF_Pos; biasref = (adcFuse & uint32(0x7<<19)) //>> 19 // calibrate ADC1 sam.ADC1.CALIB.Set(uint16((biascomp | biasr2r | biasref) >> 16)) } // Configure configures a ADCPin to be able to be used to read data. func (a ADC) Configure(config ADCConfig) { for _, adc := range []*sam.ADC_Type{sam.ADC0, sam.ADC1} { for adc.SYNCBUSY.HasBits(sam.ADC_SYNCBUSY_CTRLB) { } // wait for sync adc.CTRLA.SetBits(sam.ADC_CTRLA_PRESCALER_DIV32 << sam.ADC_CTRLA_PRESCALER_Pos) var resolution uint32 switch config.Resolution { case 8: resolution = sam.ADC_CTRLB_RESSEL_8BIT case 10: resolution = sam.ADC_CTRLB_RESSEL_10BIT case 12: resolution = sam.ADC_CTRLB_RESSEL_12BIT case 16: resolution = sam.ADC_CTRLB_RESSEL_16BIT default: resolution = sam.ADC_CTRLB_RESSEL_12BIT } adc.CTRLB.SetBits(uint16(resolution << sam.ADC_CTRLB_RESSEL_Pos)) adc.SAMPCTRL.Set(5) // sampling Time Length for adc.SYNCBUSY.HasBits(sam.ADC_SYNCBUSY_SAMPCTRL) { } // wait for sync // No Negative input (Internal Ground) adc.INPUTCTRL.Set(sam.ADC_INPUTCTRL_MUXNEG_GND << sam.ADC_INPUTCTRL_MUXNEG_Pos) for adc.SYNCBUSY.HasBits(sam.ADC_SYNCBUSY_INPUTCTRL) { } // wait for sync // Averaging (see datasheet table in AVGCTRL register description) var samples uint32 switch config.Samples { case 1: samples = sam.ADC_AVGCTRL_SAMPLENUM_1 case 2: samples = sam.ADC_AVGCTRL_SAMPLENUM_2 case 4: samples = sam.ADC_AVGCTRL_SAMPLENUM_4 case 8: samples = sam.ADC_AVGCTRL_SAMPLENUM_8 case 16: samples = sam.ADC_AVGCTRL_SAMPLENUM_16 case 32: samples = sam.ADC_AVGCTRL_SAMPLENUM_32 case 64: samples = sam.ADC_AVGCTRL_SAMPLENUM_64 case 128: samples = sam.ADC_AVGCTRL_SAMPLENUM_128 case 256: samples = sam.ADC_AVGCTRL_SAMPLENUM_256 case 512: samples = sam.ADC_AVGCTRL_SAMPLENUM_512 case 1024: samples = sam.ADC_AVGCTRL_SAMPLENUM_1024 default: // 1 sample only (no oversampling nor averaging), adjusting result by 0 samples = sam.ADC_AVGCTRL_SAMPLENUM_1 } adc.AVGCTRL.Set(uint8(samples<= PB04 && a.Pin <= PB07) || (a.Pin >= PC00) { return sam.ADC1 } return sam.ADC0 } func (a ADC) getADCChannel() uint8 { switch a.Pin { case PA02: return 0 case PB08: return 2 case PB09: return 3 case PA04: return 4 case PA05: return 5 case PA06: return 6 case PA07: return 7 case PB00: return 12 case PB01: return 13 case PB02: return 14 case PB03: return 15 case PA09: return 17 case PA11: return 19 case PB04: return 6 case PB05: return 7 case PB06: return 8 case PB07: return 9 case PC00: return 10 case PC01: return 11 case PC02: return 4 case PC03: return 5 case PC30: return 12 case PC31: return 13 case PD00: return 14 case PD01: return 15 default: panic("Invalid ADC pin") } } // UART on the SAMD51. type UART struct { Buffer *RingBuffer Bus *sam.SERCOM_USART_INT_Type SERCOM uint8 Interrupt interrupt.Interrupt // RXC interrupt } var ( // UART0 is actually a USB CDC interface. UART0 = USBCDC{Buffer: NewRingBuffer()} ) const ( sampleRate16X = 16 lsbFirst = 1 ) // Configure the UART. func (uart UART) Configure(config UARTConfig) error { // Default baud rate to 115200. if config.BaudRate == 0 { config.BaudRate = 115200 } // determine pins if config.TX == 0 && config.RX == 0 { // use default pins config.TX = UART_TX_PIN config.RX = UART_RX_PIN } // Determine transmit pinout. txPinMode, txPad, ok := findPinPadMapping(uart.SERCOM, config.TX) if !ok { return ErrInvalidOutputPin } var txPinOut uint32 // See CTRLA.RXPO bits of the SERCOM USART peripheral (page 945-946) for how // pads are mapped to pinout values. switch txPad { case 0: txPinOut = 0 default: // TODO: flow control (RTS/CTS) return ErrInvalidOutputPin } // Determine receive pinout. rxPinMode, rxPad, ok := findPinPadMapping(uart.SERCOM, config.RX) if !ok { return ErrInvalidInputPin } // As you can see in the CTRLA.RXPO bits of the SERCOM USART peripheral // (page 945), input pins are mapped directly. rxPinOut := rxPad // configure pins config.TX.Configure(PinConfig{Mode: txPinMode}) config.RX.Configure(PinConfig{Mode: rxPinMode}) // reset SERCOM uart.Bus.CTRLA.SetBits(sam.SERCOM_USART_INT_CTRLA_SWRST) for uart.Bus.CTRLA.HasBits(sam.SERCOM_USART_INT_CTRLA_SWRST) || uart.Bus.SYNCBUSY.HasBits(sam.SERCOM_USART_INT_SYNCBUSY_SWRST) { } // set UART mode/sample rate // SERCOM_USART_CTRLA_MODE(mode) | // SERCOM_USART_CTRLA_SAMPR(sampleRate); // sam.SERCOM_USART_CTRLA_MODE_USART_INT_CLK = 1? uart.Bus.CTRLA.Set((1 << sam.SERCOM_USART_INT_CTRLA_MODE_Pos) | (1 << sam.SERCOM_USART_INT_CTRLA_SAMPR_Pos)) // sample rate of 16x // Set baud rate uart.SetBaudRate(config.BaudRate) // setup UART frame // SERCOM_USART_CTRLA_FORM( (parityMode == SERCOM_NO_PARITY ? 0 : 1) ) | // dataOrder << SERCOM_USART_CTRLA_DORD_Pos; uart.Bus.CTRLA.SetBits((0 << sam.SERCOM_USART_INT_CTRLA_FORM_Pos) | // no parity (lsbFirst << sam.SERCOM_USART_INT_CTRLA_DORD_Pos)) // data order // set UART stop bits/parity // SERCOM_USART_CTRLB_CHSIZE(charSize) | // nbStopBits << SERCOM_USART_CTRLB_SBMODE_Pos | // (parityMode == SERCOM_NO_PARITY ? 0 : parityMode) << SERCOM_USART_CTRLB_PMODE_Pos; //If no parity use default value uart.Bus.CTRLB.SetBits((0 << sam.SERCOM_USART_INT_CTRLB_CHSIZE_Pos) | // 8 bits is 0 (0 << sam.SERCOM_USART_INT_CTRLB_SBMODE_Pos) | // 1 stop bit is zero (0 << sam.SERCOM_USART_INT_CTRLB_PMODE_Pos)) // no parity // set UART pads. This is not same as pins... // SERCOM_USART_CTRLA_TXPO(txPad) | // SERCOM_USART_CTRLA_RXPO(rxPad); uart.Bus.CTRLA.SetBits((txPinOut << sam.SERCOM_USART_INT_CTRLA_TXPO_Pos) | (rxPinOut << sam.SERCOM_USART_INT_CTRLA_RXPO_Pos)) // Enable Transceiver and Receiver //sercom->USART.CTRLB.reg |= SERCOM_USART_CTRLB_TXEN | SERCOM_USART_CTRLB_RXEN ; uart.Bus.CTRLB.SetBits(sam.SERCOM_USART_INT_CTRLB_TXEN | sam.SERCOM_USART_INT_CTRLB_RXEN) // Enable USART1 port. // sercom->USART.CTRLA.bit.ENABLE = 0x1u; uart.Bus.CTRLA.SetBits(sam.SERCOM_USART_INT_CTRLA_ENABLE) for uart.Bus.SYNCBUSY.HasBits(sam.SERCOM_USART_INT_SYNCBUSY_ENABLE) { } // setup interrupt on receive uart.Bus.INTENSET.Set(sam.SERCOM_USART_INT_INTENSET_RXC) // Enable RX IRQ. // This is a small note at the bottom of the NVIC section of the datasheet: // > The integer number specified in the source refers to the respective bit // > position in the INTFLAG register of respective peripheral. // Therefore, if we only need to listen to the RXC interrupt source (in bit // position 2), we only need interrupt source 2 for this SERCOM device. uart.Interrupt.Enable() return nil } // SetBaudRate sets the communication speed for the UART. func (uart UART) SetBaudRate(br uint32) { // Asynchronous fractional mode (Table 24-2 in datasheet) // BAUD = fref / (sampleRateValue * fbaud) // (multiply by 8, to calculate fractional piece) // uint32_t baudTimes8 = (SystemCoreClock * 8) / (16 * baudrate); baud := (SERCOM_FREQ_REF * 8) / (sampleRate16X * br) // sercom->USART.BAUD.FRAC.FP = (baudTimes8 % 8); // sercom->USART.BAUD.FRAC.BAUD = (baudTimes8 / 8); uart.Bus.BAUD.Set(uint16(((baud % 8) << sam.SERCOM_USART_INT_BAUD_FRAC_MODE_FP_Pos) | ((baud / 8) << sam.SERCOM_USART_INT_BAUD_FRAC_MODE_BAUD_Pos))) } // WriteByte writes a byte of data to the UART. func (uart UART) WriteByte(c byte) error { // wait until ready to receive for !uart.Bus.INTFLAG.HasBits(sam.SERCOM_USART_INT_INTFLAG_DRE) { } uart.Bus.DATA.Set(uint32(c)) return nil } func (uart *UART) handleInterrupt(interrupt.Interrupt) { // should reset IRQ uart.Receive(byte((uart.Bus.DATA.Get() & 0xFF))) uart.Bus.INTFLAG.SetBits(sam.SERCOM_USART_INT_INTFLAG_RXC) } // I2C on the SAMD51. type I2C struct { Bus *sam.SERCOM_I2CM_Type SERCOM uint8 } // I2CConfig is used to store config info for I2C. type I2CConfig struct { Frequency uint32 SCL Pin SDA Pin } const ( // SERCOM_FREQ_REF is always reference frequency on SAMD51 regardless of CPU speed. SERCOM_FREQ_REF = 48000000 // Default rise time in nanoseconds, based on 4.7K ohm pull up resistors riseTimeNanoseconds = 125 // wire bus states wireUnknownState = 0 wireIdleState = 1 wireOwnerState = 2 wireBusyState = 3 // wire commands wireCmdNoAction = 0 wireCmdRepeatStart = 1 wireCmdRead = 2 wireCmdStop = 3 ) const i2cTimeout = 1000 // Configure is intended to setup the I2C interface. func (i2c *I2C) Configure(config I2CConfig) error { // Default I2C bus speed is 100 kHz. if config.Frequency == 0 { config.Frequency = TWI_FREQ_100KHZ } // Use default I2C pins if not set. if config.SDA == 0 && config.SCL == 0 { config.SDA = SDA_PIN config.SCL = SCL_PIN } sclPinMode, sclPad, ok := findPinPadMapping(i2c.SERCOM, config.SCL) if !ok || sclPad != 1 { // SCL must be on pad 1, according to section 36.4 of the datasheet. // Note: this is not an exhaustive test for I2C support on the pin: not // all pins support I2C. return ErrInvalidClockPin } sdaPinMode, sdaPad, ok := findPinPadMapping(i2c.SERCOM, config.SDA) if !ok || sdaPad != 0 { // SDA must be on pad 0, according to section 36.4 of the datasheet. // Note: this is not an exhaustive test for I2C support on the pin: not // all pins support I2C. return ErrInvalidDataPin } // reset SERCOM i2c.Bus.CTRLA.SetBits(sam.SERCOM_I2CM_CTRLA_SWRST) for i2c.Bus.CTRLA.HasBits(sam.SERCOM_I2CM_CTRLA_SWRST) || i2c.Bus.SYNCBUSY.HasBits(sam.SERCOM_I2CM_SYNCBUSY_SWRST) { } // Set i2c controller mode //SERCOM_I2CM_CTRLA_MODE( I2C_MASTER_OPERATION ) // sam.SERCOM_I2CM_CTRLA_MODE_I2C_MASTER = 5? i2c.Bus.CTRLA.Set(5 << sam.SERCOM_I2CM_CTRLA_MODE_Pos) // | i2c.SetBaudRate(config.Frequency) // Enable I2CM port. // sercom->USART.CTRLA.bit.ENABLE = 0x1u; i2c.Bus.CTRLA.SetBits(sam.SERCOM_I2CM_CTRLA_ENABLE) for i2c.Bus.SYNCBUSY.HasBits(sam.SERCOM_I2CM_SYNCBUSY_ENABLE) { } // set bus idle mode i2c.Bus.STATUS.SetBits(wireIdleState << sam.SERCOM_I2CM_STATUS_BUSSTATE_Pos) for i2c.Bus.SYNCBUSY.HasBits(sam.SERCOM_I2CM_SYNCBUSY_SYSOP) { } // enable pins config.SDA.Configure(PinConfig{Mode: sdaPinMode}) config.SCL.Configure(PinConfig{Mode: sclPinMode}) return nil } // SetBaudRate sets the communication speed for the I2C. func (i2c *I2C) SetBaudRate(br uint32) { // Synchronous arithmetic baudrate, via Adafruit SAMD51 implementation: // sercom->I2CM.BAUD.bit.BAUD = SERCOM_FREQ_REF / ( 2 * baudrate) - 1 ; baud := SERCOM_FREQ_REF/(2*br) - 1 i2c.Bus.BAUD.Set(baud) } // Tx does a single I2C transaction at the specified address. // It clocks out the given address, writes the bytes in w, reads back len(r) // bytes and stores them in r, and generates a stop condition on the bus. func (i2c *I2C) Tx(addr uint16, w, r []byte) error { var err error if len(w) != 0 { // send start/address for write i2c.sendAddress(addr, true) // wait until transmission complete timeout := i2cTimeout for !i2c.Bus.INTFLAG.HasBits(sam.SERCOM_I2CM_INTFLAG_MB) { timeout-- if timeout == 0 { return errI2CWriteTimeout } } // ACK received (0: ACK, 1: NACK) if i2c.Bus.STATUS.HasBits(sam.SERCOM_I2CM_STATUS_RXNACK) { return errI2CAckExpected } // write data for _, b := range w { err = i2c.WriteByte(b) if err != nil { return err } } err = i2c.signalStop() if err != nil { return err } } if len(r) != 0 { // send start/address for read i2c.sendAddress(addr, false) // wait transmission complete for !i2c.Bus.INTFLAG.HasBits(sam.SERCOM_I2CM_INTFLAG_SB) { // If the peripheral NACKS the address, the MB bit will be set. // In that case, send a stop condition and return error. if i2c.Bus.INTFLAG.HasBits(sam.SERCOM_I2CM_INTFLAG_MB) { i2c.Bus.CTRLB.SetBits(wireCmdStop << sam.SERCOM_I2CM_CTRLB_CMD_Pos) // Stop condition return errI2CAckExpected } } // ACK received (0: ACK, 1: NACK) if i2c.Bus.STATUS.HasBits(sam.SERCOM_I2CM_STATUS_RXNACK) { return errI2CAckExpected } // read first byte r[0] = i2c.readByte() for i := 1; i < len(r); i++ { // Send an ACK i2c.Bus.CTRLB.ClearBits(sam.SERCOM_I2CM_CTRLB_ACKACT) i2c.signalRead() // Read data and send the ACK r[i] = i2c.readByte() } // Send NACK to end transmission i2c.Bus.CTRLB.SetBits(sam.SERCOM_I2CM_CTRLB_ACKACT) err = i2c.signalStop() if err != nil { return err } } return nil } // WriteByte writes a single byte to the I2C bus. func (i2c *I2C) WriteByte(data byte) error { // Send data byte i2c.Bus.DATA.Set(data) // wait until transmission successful timeout := i2cTimeout for !i2c.Bus.INTFLAG.HasBits(sam.SERCOM_I2CM_INTFLAG_MB) { // check for bus error if i2c.Bus.STATUS.HasBits(sam.SERCOM_I2CM_STATUS_BUSERR) { return errI2CBusError } timeout-- if timeout == 0 { return errI2CWriteTimeout } } if i2c.Bus.STATUS.HasBits(sam.SERCOM_I2CM_STATUS_RXNACK) { return errI2CAckExpected } return nil } // sendAddress sends the address and start signal func (i2c *I2C) sendAddress(address uint16, write bool) error { data := (address << 1) if !write { data |= 1 // set read flag } // wait until bus ready timeout := i2cTimeout for !i2c.Bus.STATUS.HasBits(wireIdleState< 0 { baudRate-- } spi.Bus.BAUD.Set(uint8(baudRate)) // Enable SPI port. spi.Bus.CTRLA.SetBits(sam.SERCOM_SPIM_CTRLA_ENABLE) for spi.Bus.SYNCBUSY.HasBits(sam.SERCOM_SPIM_SYNCBUSY_ENABLE) { } return nil } // Transfer writes/reads a single byte using the SPI interface. func (spi SPI) Transfer(w byte) (byte, error) { // write data spi.Bus.DATA.Set(uint32(w)) // wait for receive for !spi.Bus.INTFLAG.HasBits(sam.SERCOM_SPIM_INTFLAG_RXC) { } // return data return byte(spi.Bus.DATA.Get()), nil } var ( ErrTxInvalidSliceSize = errors.New("SPI write and read slices must be same size") ) // Tx handles read/write operation for SPI interface. Since SPI is a syncronous write/read // interface, there must always be the same number of bytes written as bytes read. // The Tx method knows about this, and offers a few different ways of calling it. // // This form sends the bytes in tx buffer, putting the resulting bytes read into the rx buffer. // Note that the tx and rx buffers must be the same size: // // spi.Tx(tx, rx) // // This form sends the tx buffer, ignoring the result. Useful for sending "commands" that return zeros // until all the bytes in the command packet have been received: // // spi.Tx(tx, nil) // // This form sends zeros, putting the result into the rx buffer. Good for reading a "result packet": // // spi.Tx(nil, rx) // func (spi SPI) Tx(w, r []byte) error { switch { case w == nil: // read only, so write zero and read a result. spi.rx(r) case r == nil: // write only spi.tx(w) default: // write/read if len(w) != len(r) { return ErrTxInvalidSliceSize } spi.txrx(w, r) } return nil } func (spi SPI) tx(tx []byte) { for i := 0; i < len(tx); i++ { for !spi.Bus.INTFLAG.HasBits(sam.SERCOM_SPIM_INTFLAG_DRE) { } spi.Bus.DATA.Set(uint32(tx[i])) } for !spi.Bus.INTFLAG.HasBits(sam.SERCOM_SPIM_INTFLAG_TXC) { } // read to clear RXC register for spi.Bus.INTFLAG.HasBits(sam.SERCOM_SPIM_INTFLAG_RXC) { spi.Bus.DATA.Get() } } func (spi SPI) rx(rx []byte) { spi.Bus.DATA.Set(0) for !spi.Bus.INTFLAG.HasBits(sam.SERCOM_SPIM_INTFLAG_DRE) { } for i := 1; i < len(rx); i++ { spi.Bus.DATA.Set(0) for !spi.Bus.INTFLAG.HasBits(sam.SERCOM_SPIM_INTFLAG_RXC) { } rx[i-1] = byte(spi.Bus.DATA.Get()) } for !spi.Bus.INTFLAG.HasBits(sam.SERCOM_SPIM_INTFLAG_RXC) { } rx[len(rx)-1] = byte(spi.Bus.DATA.Get()) } func (spi SPI) txrx(tx, rx []byte) { spi.Bus.DATA.Set(uint32(tx[0])) for !spi.Bus.INTFLAG.HasBits(sam.SERCOM_SPIM_INTFLAG_DRE) { } for i := 1; i < len(rx); i++ { spi.Bus.DATA.Set(uint32(tx[i])) for !spi.Bus.INTFLAG.HasBits(sam.SERCOM_SPIM_INTFLAG_RXC) { } rx[i-1] = byte(spi.Bus.DATA.Get()) } for !spi.Bus.INTFLAG.HasBits(sam.SERCOM_SPIM_INTFLAG_RXC) { } rx[len(rx)-1] = byte(spi.Bus.DATA.Get()) } // The QSPI peripheral on ATSAMD51 is only available on the following pins const ( QSPI_SCK = PB10 QSPI_CS = PB11 QSPI_DATA0 = PA08 QSPI_DATA1 = PA09 QSPI_DATA2 = PA10 QSPI_DATA3 = PA11 ) // PWM const period = 0xFFFF // Configure configures a PWM pin for output. func (pwm PWM) Configure() error { // Set pin as output sam.PORT.GROUP[0].DIRSET.Set(1 << uint8(pwm.Pin)) // Set pin to low sam.PORT.GROUP[0].OUTCLR.Set(1 << uint8(pwm.Pin)) // Enable the port multiplexer for pin pwm.setPinCfg(sam.PORT_GROUP_PINCFG_PMUXEN) // Connect timer/mux to pin. pwmConfig := pwm.getMux() if pwm.Pin&1 > 0 { // odd pin, so save the even pins val := pwm.getPMux() & sam.PORT_GROUP_PMUX_PMUXE_Msk pwm.setPMux(val | uint8(pwmConfig<CTRLA.reg = TCC_CTRLA_PRESCALER_DIV256 | TCC_CTRLA_PRESCSYNC_GCLK; timer.CTRLA.SetBits(sam.TCC_CTRLA_PRESCALER_DIV256 | sam.TCC_CTRLA_PRESCSYNC_GCLK) // Use "Normal PWM" (single-slope PWM) timer.WAVE.SetBits(sam.TCC_WAVE_WAVEGEN_NPWM) // Wait for synchronization for timer.SYNCBUSY.HasBits(sam.TCC_SYNCBUSY_WAVE) { } // while (TCCx->SYNCBUSY.bit.CC0 || TCCx->SYNCBUSY.bit.CC1); for timer.SYNCBUSY.HasBits(sam.TCC_SYNCBUSY_CC0) || timer.SYNCBUSY.HasBits(sam.TCC_SYNCBUSY_CC1) { } // Set the initial value // TCCx->CC[tcChannel].reg = (uint32_t) value; pwm.setChannel(timer, 0) for timer.SYNCBUSY.HasBits(sam.TCC_SYNCBUSY_CC0) || timer.SYNCBUSY.HasBits(sam.TCC_SYNCBUSY_CC1) { } // Set the period (the number to count to (TOP) before resetting timer) //TCC0->PER.reg = period; timer.PER.Set(period) // Wait for synchronization for timer.SYNCBUSY.HasBits(sam.TCC_SYNCBUSY_PER) { } // enable timer timer.CTRLA.SetBits(sam.TCC_CTRLA_ENABLE) // Wait for synchronization for timer.SYNCBUSY.HasBits(sam.TCC_SYNCBUSY_ENABLE) { } return nil } // Set turns on the duty cycle for a PWM pin using the provided value. func (pwm PWM) Set(value uint16) { // figure out which TCCX timer for this pin timer := pwm.getTimer() if timer == nil { // The Configure call above cannot have succeeded, so simply ignore this // error. return } // Wait for synchronization for timer.SYNCBUSY.HasBits(sam.TCC_SYNCBUSY_CTRLB) { } for timer.SYNCBUSY.HasBits(sam.TCC_SYNCBUSY_CC0) || timer.SYNCBUSY.HasBits(sam.TCC_SYNCBUSY_CC1) { } // TCCx->CCBUF[tcChannel].reg = (uint32_t) value; pwm.setChannelBuffer(timer, uint32(value)) for timer.SYNCBUSY.HasBits(sam.TCC_SYNCBUSY_CC0) || timer.SYNCBUSY.HasBits(sam.TCC_SYNCBUSY_CC1) { } // TCCx->CTRLBCLR.bit.LUPD = 1; timer.CTRLBCLR.SetBits(sam.TCC_CTRLBCLR_LUPD) for timer.SYNCBUSY.HasBits(sam.TCC_SYNCBUSY_CTRLB) { } } // getPMux returns the value for the correct PMUX register for this pin. func (pwm PWM) getPMux() uint8 { return pwm.Pin.getPMux() } // setPMux sets the value for the correct PMUX register for this pin. func (pwm PWM) setPMux(val uint8) { pwm.Pin.setPMux(val) } // getPinCfg returns the value for the correct PINCFG register for this pin. func (pwm PWM) getPinCfg() uint8 { return pwm.Pin.getPinCfg() } // setPinCfg sets the value for the correct PINCFG register for this pin. func (pwm PWM) setPinCfg(val uint8) { pwm.Pin.setPinCfg(val) } // setChannel sets the value for the correct channel for PWM on this pin. func (pwm PWM) setChannel(timer *sam.TCC_Type, val uint32) { switch pwm.Pin { case PA14: timer.CC[0].Set(val) case PA15: timer.CC[1].Set(val) case PA16: timer.CC[0].Set(val) case PA17: timer.CC[1].Set(val) case PA18: timer.CC[2].Set(val) case PA19: timer.CC[3].Set(val) case PA20: timer.CC[0].Set(val) case PA21: timer.CC[1].Set(val) case PA22: timer.CC[2].Set(val) case PA23: timer.CC[3].Set(val) case PB12: timer.CC[0].Set(val) case PB13: timer.CC[1].Set(val) case PB14: timer.CC[0].Set(val) case PB15: timer.CC[1].Set(val) case PB16: timer.CC[4].Set(val) case PB17: timer.CC[5].Set(val) case PB31: timer.CC[1].Set(val) default: return // not supported on this pin } } // setChannelBuffer sets the value for the correct channel buffer for PWM on this pin func (pwm PWM) setChannelBuffer(timer *sam.TCC_Type, val uint32) { switch pwm.Pin { case PA14: timer.CCBUF[0].Set(val) case PA15: timer.CCBUF[1].Set(val) case PA16: timer.CCBUF[0].Set(val) case PA17: timer.CCBUF[1].Set(val) case PA18: timer.CCBUF[2].Set(val) case PA19: timer.CCBUF[3].Set(val) case PA20: timer.CCBUF[0].Set(val) case PA21: timer.CCBUF[1].Set(val) case PA22: timer.CCBUF[2].Set(val) case PA23: timer.CCBUF[3].Set(val) case PB12: timer.CCBUF[0].Set(val) case PB13: timer.CCBUF[1].Set(val) case PB14: timer.CCBUF[0].Set(val) case PB15: timer.CCBUF[1].Set(val) case PB16: timer.CCBUF[4].Set(val) case PB17: timer.CCBUF[5].Set(val) case PB31: timer.CCBUF[1].Set(val) default: return // not supported on this pin } } // getMux returns the pin mode mux to be used for PWM on this pin. func (pwm PWM) getMux() PinMode { switch pwm.Pin { case PA14: return PinPWMF case PA15: return PinPWMF case PA16: return PinPWMF case PA17: return PinPWMF case PA18: return PinPWMF case PA19: return PinPWMF case PA20: return PinPWMG case PA21: return PinPWMG case PA22: return PinPWMG case PA23: return PinPWMG case PB12: return PinPWMF case PB13: return PinPWMF case PB14: return PinPWMF case PB15: return PinPWMF case PB16: return PinPWMG case PB17: return PinPWMG case PB31: return PinPWMF default: return 0 // not supported on this pin } } // USBCDC is the USB CDC aka serial over USB interface on the SAMD21. type USBCDC struct { Buffer *RingBuffer TxIdx volatile.Register8 waitTxc bool waitTxcRetryCount uint8 sent bool } const ( usbcdcTxSizeMask uint8 = 0x3F usbcdcTxBankMask uint8 = ^usbcdcTxSizeMask usbcdcTxBank1st uint8 = 0x00 usbcdcTxBank2nd uint8 = usbcdcTxSizeMask + 1 usbcdcTxMaxRetriesAllowed uint8 = 5 ) // Flush flushes buffered data. func (usbcdc *USBCDC) Flush() error { if usbLineInfo.lineState > 0 { idx := usbcdc.TxIdx.Get() sz := idx & usbcdcTxSizeMask bk := idx & usbcdcTxBankMask if 0 < sz { if usbcdc.waitTxc { // waiting for the next flush(), because the transmission is not complete return nil } usbcdc.waitTxc = true usbcdc.waitTxcRetryCount = 0 // set the data usbEndpointDescriptors[usb_CDC_ENDPOINT_IN].DeviceDescBank[1].ADDR.Set(uint32(uintptr(unsafe.Pointer(&udd_ep_in_cache_buffer[usb_CDC_ENDPOINT_IN][bk])))) if bk == usbcdcTxBank1st { usbcdc.TxIdx.Set(usbcdcTxBank2nd) } else { usbcdc.TxIdx.Set(usbcdcTxBank1st) } // clean multi packet size of bytes already sent usbEndpointDescriptors[usb_CDC_ENDPOINT_IN].DeviceDescBank[1].PCKSIZE.ClearBits(usb_DEVICE_PCKSIZE_MULTI_PACKET_SIZE_Mask << usb_DEVICE_PCKSIZE_MULTI_PACKET_SIZE_Pos) // set count of bytes to be sent usbEndpointDescriptors[usb_CDC_ENDPOINT_IN].DeviceDescBank[1].PCKSIZE.ClearBits(usb_DEVICE_PCKSIZE_BYTE_COUNT_Mask << usb_DEVICE_PCKSIZE_BYTE_COUNT_Pos) usbEndpointDescriptors[usb_CDC_ENDPOINT_IN].DeviceDescBank[1].PCKSIZE.SetBits((uint32(sz) & usb_DEVICE_PCKSIZE_BYTE_COUNT_Mask) << usb_DEVICE_PCKSIZE_BYTE_COUNT_Pos) // clear transfer complete flag setEPINTFLAG(usb_CDC_ENDPOINT_IN, sam.USB_DEVICE_ENDPOINT_EPINTFLAG_TRCPT1) // send data by setting bank ready setEPSTATUSSET(usb_CDC_ENDPOINT_IN, sam.USB_DEVICE_ENDPOINT_EPSTATUSSET_BK1RDY) UART0.sent = true } } return nil } // WriteByte writes a byte of data to the USB CDC interface. func (usbcdc *USBCDC) WriteByte(c byte) error { // Supposedly to handle problem with Windows USB serial ports? if usbLineInfo.lineState > 0 { ok := false for { mask := interrupt.Disable() idx := UART0.TxIdx.Get() if (idx & usbcdcTxSizeMask) < usbcdcTxSizeMask { udd_ep_in_cache_buffer[usb_CDC_ENDPOINT_IN][idx] = c UART0.TxIdx.Set(idx + 1) ok = true } interrupt.Restore(mask) if ok { break } else if usbcdcTxMaxRetriesAllowed < UART0.waitTxcRetryCount { mask := interrupt.Disable() UART0.waitTxc = false UART0.waitTxcRetryCount = 0 usbcdc.TxIdx.Set(0) usbLineInfo.lineState = 0 interrupt.Restore(mask) break } else { mask := interrupt.Disable() if UART0.sent { if UART0.waitTxc { if (getEPINTFLAG(usb_CDC_ENDPOINT_IN) & sam.USB_DEVICE_ENDPOINT_EPINTFLAG_TRCPT1) != 0 { setEPSTATUSCLR(usb_CDC_ENDPOINT_IN, sam.USB_DEVICE_ENDPOINT_EPSTATUSCLR_BK1RDY) setEPINTFLAG(usb_CDC_ENDPOINT_IN, sam.USB_DEVICE_ENDPOINT_EPINTFLAG_TRCPT1) UART0.waitTxc = false UART0.Flush() } } else { UART0.Flush() } } interrupt.Restore(mask) } } } return nil } func (usbcdc USBCDC) DTR() bool { return (usbLineInfo.lineState & usb_CDC_LINESTATE_DTR) > 0 } func (usbcdc USBCDC) RTS() bool { return (usbLineInfo.lineState & usb_CDC_LINESTATE_RTS) > 0 } const ( // these are SAMD51 specific. usb_DEVICE_PCKSIZE_BYTE_COUNT_Pos = 0 usb_DEVICE_PCKSIZE_BYTE_COUNT_Mask = 0x3FFF usb_DEVICE_PCKSIZE_SIZE_Pos = 28 usb_DEVICE_PCKSIZE_SIZE_Mask = 0x7 usb_DEVICE_PCKSIZE_MULTI_PACKET_SIZE_Pos = 14 usb_DEVICE_PCKSIZE_MULTI_PACKET_SIZE_Mask = 0x3FFF ) var ( usbEndpointDescriptors [8]usbDeviceDescriptor udd_ep_in_cache_buffer [7][128]uint8 udd_ep_out_cache_buffer [7][128]uint8 isEndpointHalt = false isRemoteWakeUpEnabled = false endPoints = []uint32{usb_ENDPOINT_TYPE_CONTROL, (usb_ENDPOINT_TYPE_INTERRUPT | usbEndpointIn), (usb_ENDPOINT_TYPE_BULK | usbEndpointOut), (usb_ENDPOINT_TYPE_BULK | usbEndpointIn)} usbConfiguration uint8 usbSetInterface uint8 usbLineInfo = cdcLineInfo{115200, 0x00, 0x00, 0x08, 0x00} ) // Configure the USB CDC interface. The config is here for compatibility with the UART interface. func (usbcdc USBCDC) Configure(config UARTConfig) { // reset USB interface sam.USB_DEVICE.CTRLA.SetBits(sam.USB_DEVICE_CTRLA_SWRST) for sam.USB_DEVICE.SYNCBUSY.HasBits(sam.USB_DEVICE_SYNCBUSY_SWRST) || sam.USB_DEVICE.SYNCBUSY.HasBits(sam.USB_DEVICE_SYNCBUSY_ENABLE) { } sam.USB_DEVICE.DESCADD.Set(uint32(uintptr(unsafe.Pointer(&usbEndpointDescriptors)))) // configure pins USBCDC_DM_PIN.Configure(PinConfig{Mode: PinCom}) USBCDC_DP_PIN.Configure(PinConfig{Mode: PinCom}) // performs pad calibration from store fuses handlePadCalibration() // run in standby sam.USB_DEVICE.CTRLA.SetBits(sam.USB_DEVICE_CTRLA_RUNSTDBY) // set full speed sam.USB_DEVICE.CTRLB.SetBits(sam.USB_DEVICE_CTRLB_SPDCONF_FS << sam.USB_DEVICE_CTRLB_SPDCONF_Pos) // attach sam.USB_DEVICE.CTRLB.ClearBits(sam.USB_DEVICE_CTRLB_DETACH) // enable interrupt for end of reset sam.USB_DEVICE.INTENSET.SetBits(sam.USB_DEVICE_INTENSET_EORST) // enable interrupt for start of frame sam.USB_DEVICE.INTENSET.SetBits(sam.USB_DEVICE_INTENSET_SOF) // enable USB sam.USB_DEVICE.CTRLA.SetBits(sam.USB_DEVICE_CTRLA_ENABLE) // enable IRQ at highest priority interrupt.New(sam.IRQ_USB_OTHER, handleUSBIRQ).Enable() interrupt.New(sam.IRQ_USB_SOF_HSOF, handleUSBIRQ).Enable() interrupt.New(sam.IRQ_USB_TRCPT0, handleUSBIRQ).Enable() interrupt.New(sam.IRQ_USB_TRCPT1, handleUSBIRQ).Enable() } func handlePadCalibration() { // Load Pad Calibration data from non-volatile memory // This requires registers that are not included in the SVD file. // Modeled after defines from samd21g18a.h and nvmctrl.h: // // #define NVMCTRL_OTP4 0x00806020 // // #define USB_FUSES_TRANSN_ADDR (NVMCTRL_OTP4 + 4) // #define USB_FUSES_TRANSN_Pos 13 /**< \brief (NVMCTRL_OTP4) USB pad Transn calibration */ // #define USB_FUSES_TRANSN_Msk (0x1Fu << USB_FUSES_TRANSN_Pos) // #define USB_FUSES_TRANSN(value) ((USB_FUSES_TRANSN_Msk & ((value) << USB_FUSES_TRANSN_Pos))) // #define USB_FUSES_TRANSP_ADDR (NVMCTRL_OTP4 + 4) // #define USB_FUSES_TRANSP_Pos 18 /**< \brief (NVMCTRL_OTP4) USB pad Transp calibration */ // #define USB_FUSES_TRANSP_Msk (0x1Fu << USB_FUSES_TRANSP_Pos) // #define USB_FUSES_TRANSP(value) ((USB_FUSES_TRANSP_Msk & ((value) << USB_FUSES_TRANSP_Pos))) // #define USB_FUSES_TRIM_ADDR (NVMCTRL_OTP4 + 4) // #define USB_FUSES_TRIM_Pos 23 /**< \brief (NVMCTRL_OTP4) USB pad Trim calibration */ // #define USB_FUSES_TRIM_Msk (0x7u << USB_FUSES_TRIM_Pos) // #define USB_FUSES_TRIM(value) ((USB_FUSES_TRIM_Msk & ((value) << USB_FUSES_TRIM_Pos))) // fuse := *(*uint32)(unsafe.Pointer(uintptr(0x00806020) + 4)) calibTransN := uint16(fuse>>13) & uint16(0x1f) calibTransP := uint16(fuse>>18) & uint16(0x1f) calibTrim := uint16(fuse>>23) & uint16(0x7) if calibTransN == 0x1f { calibTransN = 5 } sam.USB_DEVICE.PADCAL.SetBits(calibTransN << sam.USB_DEVICE_PADCAL_TRANSN_Pos) if calibTransP == 0x1f { calibTransP = 29 } sam.USB_DEVICE.PADCAL.SetBits(calibTransP << sam.USB_DEVICE_PADCAL_TRANSP_Pos) if calibTrim == 0x7 { calibTransN = 3 } sam.USB_DEVICE.PADCAL.SetBits(calibTrim << sam.USB_DEVICE_PADCAL_TRIM_Pos) } func handleUSBIRQ(interrupt.Interrupt) { // reset all interrupt flags flags := sam.USB_DEVICE.INTFLAG.Get() sam.USB_DEVICE.INTFLAG.Set(flags) // End of reset if (flags & sam.USB_DEVICE_INTFLAG_EORST) > 0 { // Configure control endpoint initEndpoint(0, usb_ENDPOINT_TYPE_CONTROL) // Enable Setup-Received interrupt setEPINTENSET(0, sam.USB_DEVICE_ENDPOINT_EPINTENSET_RXSTP) usbConfiguration = 0 // ack the End-Of-Reset interrupt sam.USB_DEVICE.INTFLAG.Set(sam.USB_DEVICE_INTFLAG_EORST) } // Start of frame if (flags & sam.USB_DEVICE_INTFLAG_SOF) > 0 { // if you want to blink LED showing traffic, this would be the place... } // Endpoint 0 Setup interrupt if getEPINTFLAG(0)&sam.USB_DEVICE_ENDPOINT_EPINTFLAG_RXSTP > 0 { // ack setup received setEPINTFLAG(0, sam.USB_DEVICE_ENDPOINT_EPINTFLAG_RXSTP) // parse setup setup := newUSBSetup(udd_ep_out_cache_buffer[0][:]) // Clear the Bank 0 ready flag on Control OUT setEPSTATUSCLR(0, sam.USB_DEVICE_ENDPOINT_EPSTATUSCLR_BK0RDY) usbEndpointDescriptors[0].DeviceDescBank[0].PCKSIZE.ClearBits(usb_DEVICE_PCKSIZE_BYTE_COUNT_Mask << usb_DEVICE_PCKSIZE_BYTE_COUNT_Pos) ok := false if (setup.bmRequestType & usb_REQUEST_TYPE) == usb_REQUEST_STANDARD { // Standard Requests ok = handleStandardSetup(setup) } else { // Class Interface Requests if setup.wIndex == usb_CDC_ACM_INTERFACE { ok = cdcSetup(setup) } } if ok { // set Bank1 ready setEPSTATUSSET(0, sam.USB_DEVICE_ENDPOINT_EPSTATUSSET_BK1RDY) } else { // Stall endpoint setEPSTATUSSET(0, sam.USB_DEVICE_ENDPOINT_EPINTFLAG_STALL1) } if getEPINTFLAG(0)&sam.USB_DEVICE_ENDPOINT_EPINTFLAG_STALL1 > 0 { // ack the stall setEPINTFLAG(0, sam.USB_DEVICE_ENDPOINT_EPINTFLAG_STALL1) // clear stall request setEPINTENCLR(0, sam.USB_DEVICE_ENDPOINT_EPINTENCLR_STALL1) } } // Now the actual transfer handlers, ignore endpoint number 0 (setup) var i uint32 for i = 1; i < uint32(len(endPoints)); i++ { // Check if endpoint has a pending interrupt epFlags := getEPINTFLAG(i) if (epFlags&sam.USB_DEVICE_ENDPOINT_EPINTFLAG_TRCPT0) > 0 || (epFlags&sam.USB_DEVICE_ENDPOINT_EPINTFLAG_TRCPT1) > 0 { switch i { case usb_CDC_ENDPOINT_OUT: handleEndpoint(i) setEPINTFLAG(i, epFlags) case usb_CDC_ENDPOINT_IN, usb_CDC_ENDPOINT_ACM: setEPSTATUSCLR(i, sam.USB_DEVICE_ENDPOINT_EPSTATUSCLR_BK1RDY) setEPINTFLAG(i, sam.USB_DEVICE_ENDPOINT_EPINTFLAG_TRCPT1) if i == usb_CDC_ENDPOINT_IN { UART0.waitTxc = false } } } if i == usb_CDC_ENDPOINT_IN && UART0.waitTxc { UART0.waitTxcRetryCount++ } } UART0.Flush() } func initEndpoint(ep, config uint32) { switch config { case usb_ENDPOINT_TYPE_INTERRUPT | usbEndpointIn: // set packet size usbEndpointDescriptors[ep].DeviceDescBank[1].PCKSIZE.SetBits(epPacketSize(64) << usb_DEVICE_PCKSIZE_SIZE_Pos) // set data buffer address usbEndpointDescriptors[ep].DeviceDescBank[1].ADDR.Set(uint32(uintptr(unsafe.Pointer(&udd_ep_in_cache_buffer[ep])))) // set endpoint type setEPCFG(ep, ((usb_ENDPOINT_TYPE_INTERRUPT + 1) << sam.USB_DEVICE_ENDPOINT_EPCFG_EPTYPE1_Pos)) case usb_ENDPOINT_TYPE_BULK | usbEndpointOut: // set packet size usbEndpointDescriptors[ep].DeviceDescBank[0].PCKSIZE.SetBits(epPacketSize(64) << usb_DEVICE_PCKSIZE_SIZE_Pos) // set data buffer address usbEndpointDescriptors[ep].DeviceDescBank[0].ADDR.Set(uint32(uintptr(unsafe.Pointer(&udd_ep_out_cache_buffer[ep])))) // set endpoint type setEPCFG(ep, ((usb_ENDPOINT_TYPE_BULK + 1) << sam.USB_DEVICE_ENDPOINT_EPCFG_EPTYPE0_Pos)) // receive interrupts when current transfer complete setEPINTENSET(ep, sam.USB_DEVICE_ENDPOINT_EPINTENSET_TRCPT0) // set byte count to zero, we have not received anything yet usbEndpointDescriptors[ep].DeviceDescBank[0].PCKSIZE.ClearBits(usb_DEVICE_PCKSIZE_BYTE_COUNT_Mask << usb_DEVICE_PCKSIZE_BYTE_COUNT_Pos) // ready for next transfer setEPSTATUSCLR(ep, sam.USB_DEVICE_ENDPOINT_EPSTATUSCLR_BK0RDY) case usb_ENDPOINT_TYPE_INTERRUPT | usbEndpointOut: // TODO: not really anything, seems like... case usb_ENDPOINT_TYPE_BULK | usbEndpointIn: // set packet size usbEndpointDescriptors[ep].DeviceDescBank[1].PCKSIZE.SetBits(epPacketSize(64) << usb_DEVICE_PCKSIZE_SIZE_Pos) // set data buffer address usbEndpointDescriptors[ep].DeviceDescBank[1].ADDR.Set(uint32(uintptr(unsafe.Pointer(&udd_ep_in_cache_buffer[ep])))) // set endpoint type setEPCFG(ep, ((usb_ENDPOINT_TYPE_BULK + 1) << sam.USB_DEVICE_ENDPOINT_EPCFG_EPTYPE1_Pos)) // NAK on endpoint IN, the bank is not yet filled in. setEPSTATUSCLR(ep, sam.USB_DEVICE_ENDPOINT_EPSTATUSCLR_BK1RDY) case usb_ENDPOINT_TYPE_CONTROL: // Control OUT // set packet size usbEndpointDescriptors[ep].DeviceDescBank[0].PCKSIZE.SetBits(epPacketSize(64) << usb_DEVICE_PCKSIZE_SIZE_Pos) // set data buffer address usbEndpointDescriptors[ep].DeviceDescBank[0].ADDR.Set(uint32(uintptr(unsafe.Pointer(&udd_ep_out_cache_buffer[ep])))) // set endpoint type setEPCFG(ep, getEPCFG(ep)|((usb_ENDPOINT_TYPE_CONTROL+1)<> 8) b[2] = byte(usbLineInfo.dwDTERate >> 16) b[3] = byte(usbLineInfo.dwDTERate >> 24) b[4] = byte(usbLineInfo.bCharFormat) b[5] = byte(usbLineInfo.bParityType) b[6] = byte(usbLineInfo.bDataBits) sendUSBPacket(0, b) return true } } if setup.bmRequestType == usb_REQUEST_HOSTTODEVICE_CLASS_INTERFACE { if setup.bRequest == usb_CDC_SET_LINE_CODING { b := receiveUSBControlPacket() usbLineInfo.dwDTERate = uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 | uint32(b[3])<<24 usbLineInfo.bCharFormat = b[4] usbLineInfo.bParityType = b[5] usbLineInfo.bDataBits = b[6] } if setup.bRequest == usb_CDC_SET_CONTROL_LINE_STATE { usbLineInfo.lineState = setup.wValueL } if setup.bRequest == usb_CDC_SET_LINE_CODING || setup.bRequest == usb_CDC_SET_CONTROL_LINE_STATE { // auto-reset into the bootloader if usbLineInfo.dwDTERate == 1200 && usbLineInfo.lineState&usb_CDC_LINESTATE_DTR == 0 { ResetProcessor() } else { // TODO: cancel any reset } sendZlp() } if setup.bRequest == usb_CDC_SEND_BREAK { // TODO: something with this value? // breakValue = ((uint16_t)setup.wValueH << 8) | setup.wValueL; // return false; sendZlp() } return true } return false } //go:noinline func sendUSBPacket(ep uint32, data []byte) { copy(udd_ep_in_cache_buffer[ep][:], data) // Set endpoint address for sending data usbEndpointDescriptors[ep].DeviceDescBank[1].ADDR.Set(uint32(uintptr(unsafe.Pointer(&udd_ep_in_cache_buffer[ep])))) // clear multi-packet size which is total bytes already sent usbEndpointDescriptors[ep].DeviceDescBank[1].PCKSIZE.ClearBits(usb_DEVICE_PCKSIZE_MULTI_PACKET_SIZE_Mask << usb_DEVICE_PCKSIZE_MULTI_PACKET_SIZE_Pos) // set byte count, which is total number of bytes to be sent usbEndpointDescriptors[ep].DeviceDescBank[1].PCKSIZE.ClearBits(usb_DEVICE_PCKSIZE_BYTE_COUNT_Mask << usb_DEVICE_PCKSIZE_BYTE_COUNT_Pos) usbEndpointDescriptors[ep].DeviceDescBank[1].PCKSIZE.SetBits(uint32((len(data) & usb_DEVICE_PCKSIZE_BYTE_COUNT_Mask) << usb_DEVICE_PCKSIZE_BYTE_COUNT_Pos)) } func receiveUSBControlPacket() []byte { // address usbEndpointDescriptors[0].DeviceDescBank[0].ADDR.Set(uint32(uintptr(unsafe.Pointer(&udd_ep_out_cache_buffer[0])))) // set byte count to zero usbEndpointDescriptors[0].DeviceDescBank[0].PCKSIZE.ClearBits(usb_DEVICE_PCKSIZE_BYTE_COUNT_Mask << usb_DEVICE_PCKSIZE_BYTE_COUNT_Pos) // set ready for next data setEPSTATUSCLR(0, sam.USB_DEVICE_ENDPOINT_EPSTATUSCLR_BK0RDY) // Wait until OUT transfer is ready. timeout := 300000 for (getEPSTATUS(0) & sam.USB_DEVICE_ENDPOINT_EPSTATUS_BK0RDY) == 0 { timeout-- if timeout == 0 { return []byte{} } } // Wait until OUT transfer is completed. timeout = 300000 for (getEPINTFLAG(0) & sam.USB_DEVICE_ENDPOINT_EPINTFLAG_TRCPT1) == 0 { timeout-- if timeout == 0 { return []byte{} } } // get data bytesread := uint32((usbEndpointDescriptors[0].DeviceDescBank[0].PCKSIZE.Get() >> usb_DEVICE_PCKSIZE_BYTE_COUNT_Pos) & usb_DEVICE_PCKSIZE_BYTE_COUNT_Mask) data := make([]byte, bytesread) copy(data, udd_ep_out_cache_buffer[0][:]) return data } func handleEndpoint(ep uint32) { // get data count := int((usbEndpointDescriptors[ep].DeviceDescBank[0].PCKSIZE.Get() >> usb_DEVICE_PCKSIZE_BYTE_COUNT_Pos) & usb_DEVICE_PCKSIZE_BYTE_COUNT_Mask) // move to ring buffer for i := 0; i < count; i++ { UART0.Receive(byte((udd_ep_out_cache_buffer[ep][i] & 0xFF))) } // set byte count to zero usbEndpointDescriptors[ep].DeviceDescBank[0].PCKSIZE.ClearBits(usb_DEVICE_PCKSIZE_BYTE_COUNT_Mask << usb_DEVICE_PCKSIZE_BYTE_COUNT_Pos) // set multi packet size to 64 usbEndpointDescriptors[ep].DeviceDescBank[0].PCKSIZE.SetBits(64 << usb_DEVICE_PCKSIZE_MULTI_PACKET_SIZE_Pos) // set ready for next data setEPSTATUSCLR(ep, sam.USB_DEVICE_ENDPOINT_EPSTATUSCLR_BK0RDY) } func sendZlp() { usbEndpointDescriptors[0].DeviceDescBank[1].PCKSIZE.ClearBits(usb_DEVICE_PCKSIZE_BYTE_COUNT_Mask << usb_DEVICE_PCKSIZE_BYTE_COUNT_Pos) } func epPacketSize(size uint16) uint32 { switch size { case 8: return 0 case 16: return 1 case 32: return 2 case 64: return 3 case 128: return 4 case 256: return 5 case 512: return 6 case 1023: return 7 default: return 0 } } func getEPCFG(ep uint32) uint8 { return sam.USB_DEVICE.DEVICE_ENDPOINT[ep].EPCFG.Get() } func setEPCFG(ep uint32, val uint8) { sam.USB_DEVICE.DEVICE_ENDPOINT[ep].EPCFG.Set(val) } func setEPSTATUSCLR(ep uint32, val uint8) { sam.USB_DEVICE.DEVICE_ENDPOINT[ep].EPSTATUSCLR.Set(val) } func setEPSTATUSSET(ep uint32, val uint8) { sam.USB_DEVICE.DEVICE_ENDPOINT[ep].EPSTATUSSET.Set(val) } func getEPSTATUS(ep uint32) uint8 { return sam.USB_DEVICE.DEVICE_ENDPOINT[ep].EPSTATUS.Get() } func getEPINTFLAG(ep uint32) uint8 { return sam.USB_DEVICE.DEVICE_ENDPOINT[ep].EPINTFLAG.Get() } func setEPINTFLAG(ep uint32, val uint8) { sam.USB_DEVICE.DEVICE_ENDPOINT[ep].EPINTFLAG.Set(val) } func setEPINTENCLR(ep uint32, val uint8) { sam.USB_DEVICE.DEVICE_ENDPOINT[ep].EPINTENCLR.Set(val) } func setEPINTENSET(ep uint32, val uint8) { sam.USB_DEVICE.DEVICE_ENDPOINT[ep].EPINTENSET.Set(val) } // ResetProcessor should perform a system reset in preparation // to switch to the bootloader to flash new firmware. func ResetProcessor() { arm.DisableInterrupts() // Perform magic reset into bootloader, as mentioned in // https://github.com/arduino/ArduinoCore-samd/issues/197 *(*uint32)(unsafe.Pointer(uintptr(0x20000000 + HSRAM_SIZE - 4))) = RESET_MAGIC_VALUE arm.SystemReset() } // DAC on the SAMD51. type DAC struct { } var ( DAC0 = DAC{} ) // DACConfig placeholder for future expansion. type DACConfig struct { } // Configure the DAC. // output pin must already be configured. func (dac DAC) Configure(config DACConfig) { // Turn on clock for DAC sam.MCLK.APBDMASK.SetBits(sam.MCLK_APBDMASK_DAC_) // Use Generic Clock Generator 4 as source for DAC. sam.GCLK.PCHCTRL[42].Set((sam.GCLK_PCHCTRL_GEN_GCLK4 << sam.GCLK_PCHCTRL_GEN_Pos) | sam.GCLK_PCHCTRL_CHEN) for sam.GCLK.SYNCBUSY.HasBits(sam.GCLK_SYNCBUSY_GENCTRL_GCLK4 << sam.GCLK_SYNCBUSY_GENCTRL_Pos) { } // reset DAC sam.DAC.CTRLA.Set(sam.DAC_CTRLA_SWRST) // wait for reset complete for sam.DAC.CTRLA.HasBits(sam.DAC_CTRLA_SWRST) { } for sam.DAC.SYNCBUSY.HasBits(sam.DAC_SYNCBUSY_SWRST) { } // enable sam.DAC.CTRLB.Set(sam.DAC_CTRLB_REFSEL_VREFPU << sam.DAC_CTRLB_REFSEL_Pos) sam.DAC.DACCTRL[0].SetBits((sam.DAC_DACCTRL_CCTRL_CC12M << sam.DAC_DACCTRL_CCTRL_Pos) | sam.DAC_DACCTRL_ENABLE) sam.DAC.CTRLA.Set(sam.DAC_CTRLA_ENABLE) for sam.DAC.SYNCBUSY.HasBits(sam.DAC_SYNCBUSY_ENABLE) { } for !sam.DAC.STATUS.HasBits(sam.DAC_STATUS_READY0) { } } // Set writes a single 16-bit value to the DAC. // Since the ATSAMD51 only has a 12-bit DAC, the passed-in value will be scaled down. func (dac DAC) Set(value uint16) error { sam.DAC.DATA[0].Set(value >> 4) syncDAC() return nil } func syncDAC() { for !sam.DAC.STATUS.HasBits(sam.DAC_STATUS_EOC0) { } for sam.DAC.SYNCBUSY.HasBits(sam.DAC_SYNCBUSY_DATA0) { } }