8cd2a462b9
There is no reason to specialize this per chip as it is only ever used for JavaScript. Not only that, it is causing confusion and is yet another quirk to learn when porting the runtime to a new microcontroller.
91 строка
1,5 КиБ
Go
91 строка
1,5 КиБ
Go
// +build avr
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package runtime
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import (
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"device/avr"
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"unsafe"
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)
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const BOARD = "arduino"
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type timeUnit uint32
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var currentTime timeUnit
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// Watchdog timer periods. These can be off by a large margin (hence the jump
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// between 64ms and 125ms which is not an exact double), so don't rely on this
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// for accurate time keeping.
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const (
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WDT_PERIOD_16MS = iota
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WDT_PERIOD_32MS
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WDT_PERIOD_64MS
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WDT_PERIOD_125MS
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WDT_PERIOD_250MS
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WDT_PERIOD_500MS
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WDT_PERIOD_1S
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WDT_PERIOD_2S
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)
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//go:extern _sbss
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var _sbss [0]byte
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//go:extern _ebss
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var _ebss [0]byte
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//export main
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func main() {
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preinit()
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run()
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abort()
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}
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func preinit() {
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// Initialize .bss: zero-initialized global variables.
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ptr := unsafe.Pointer(&_sbss)
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for ptr != unsafe.Pointer(&_ebss) {
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*(*uint8)(ptr) = 0
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ptr = unsafe.Pointer(uintptr(ptr) + 1)
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}
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}
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func postinit() {
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// Enable interrupts after initialization.
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avr.Asm("sei")
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}
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func init() {
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initUART()
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}
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const tickNanos = 1024 * 16384 // roughly 16ms in nanoseconds
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func ticksToNanoseconds(ticks timeUnit) int64 {
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return int64(ticks) * tickNanos
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}
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func nanosecondsToTicks(ns int64) timeUnit {
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return timeUnit(ns / tickNanos)
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}
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// Sleep this number of ticks of 16ms.
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//
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// TODO: not very accurate. Improve accuracy by calibrating on startup and every
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// once in a while.
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func sleepTicks(d timeUnit) {
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currentTime += d
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for d != 0 {
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sleepWDT(WDT_PERIOD_16MS)
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d -= 1
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}
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}
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func ticks() timeUnit {
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return currentTime
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}
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func abort() {
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for {
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sleepWDT(WDT_PERIOD_2S)
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}
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}
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