tinygo/src/runtime/runtime_nrf_softdevice.go
Ayke van Laethem 9d625a1ccb nrf: call sd_app_evt_wait when the SoftDevice is enabled
This reduces current consumption from 500-1000µA to very low (<10µA)
current consumption. This change is important for battery powered
devices, especially devices that may be running for long periods of
time.
2020-08-24 22:46:21 +02:00

40 строки
1,1 КиБ
Go

// +build nrf,softdevice
package runtime
import (
"device/arm"
"device/nrf"
)
//export sd_app_evt_wait
func sd_app_evt_wait()
func waitForEvents() {
// Call into the SoftDevice to sleep. This is necessary here because a
// normal wfe will not put the chip in low power mode (it still consumes
// 500µA-1mA). It is really needed to call sd_app_evt_wait for low power
// consumption.
// First check whether the SoftDevice is enabled. Unfortunately,
// sd_app_evt_wait cannot be called when the SoftDevice is not enabled.
var enabled uint8
arm.SVCall1(0x12, &enabled) // sd_softdevice_is_enabled
if enabled != 0 {
// Now pick the appropriate SVCall number. Hopefully they won't change
// in the future with a different SoftDevice version.
if nrf.DEVICE == "nrf51" {
// sd_app_evt_wait: SOC_SVC_BASE_NOT_AVAILABLE + 29
arm.SVCall0(0x2B + 29)
} else if nrf.DEVICE == "nrf52" || nrf.DEVICE == "nrf52840" {
// sd_app_evt_wait: SOC_SVC_BASE_NOT_AVAILABLE + 21
arm.SVCall0(0x2C + 21)
} else {
sd_app_evt_wait()
}
} else {
// SoftDevice is disabled so we can sleep normally.
arm.Asm("wfe")
}
}