tinygo-org/tinygo
1
0
Fork 0
mirror of https://github.com/tinygo-org/tinygo.git synced 2026-08-13 15:33:40 +00:00
Code Issues Packages Projects Releases 6 Wiki Activity

sam: return an error when an incorrect PWM pin is used

Browse Source 
Previously it would trigger a nil pointer panic.
This commit is contained in:
Ayke van Laethem
2020-05-11 16:02:00 +02:00
committed by Ron Evans
parent b5f028e1f7
commit 38fc340802
7 changed files with 84 additions and 51 deletions
Download Patch File Download Diff File Expand all files Collapse all files
src/machine/machine_atsamd51.go
+38 -28
View File
@@ -1216,7 +1216,7 @@ const (
const period = 0xFFFF
// Configure configures a PWM pin for output.
func (pwm PWM) Configure() {
func (pwm PWM) Configure() error {
// Set pin as output
sam.PORT.GROUP[0].DIRSET.Set(1 << uint8(pwm.Pin))
// Set pin to low
@@ -1240,6 +1240,9 @@ func (pwm PWM) Configure() {
// figure out which TCCX timer for this pin
timer := pwm.getTimer()
if timer == nil {
return ErrInvalidOutputPin
}
// disable timer
timer.CTRLA.ClearBits(sam.TCC_CTRLA_ENABLE)
@@ -1264,7 +1267,7 @@ func (pwm PWM) Configure() {
// Set the initial value
// TCCx->CC[tcChannel].reg = (uint32_t) value;
pwm.setChannel(0)
pwm.setChannel(timer, 0)
for timer.SYNCBUSY.HasBits(sam.TCC_SYNCBUSY_CC0) ||
timer.SYNCBUSY.HasBits(sam.TCC_SYNCBUSY_CC1) {
@@ -1282,12 +1285,19 @@ func (pwm PWM) Configure() {
// 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) {
@@ -1297,7 +1307,7 @@ func (pwm PWM) Set(value uint16) {
}
// TCCx->CCBUF[tcChannel].reg = (uint32_t) value;
pwm.setChannelBuffer(uint32(value))
pwm.setChannelBuffer(timer, uint32(value))
for timer.SYNCBUSY.HasBits(sam.TCC_SYNCBUSY_CC0) ||
timer.SYNCBUSY.HasBits(sam.TCC_SYNCBUSY_CC1) {
@@ -1329,61 +1339,61 @@ 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(val uint32) {
// 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 PA16:
pwm.getTimer().CC[0].Set(val)
timer.CC[0].Set(val)
case PA17:
pwm.getTimer().CC[1].Set(val)
timer.CC[1].Set(val)
case PA14:
pwm.getTimer().CC[0].Set(val)
timer.CC[0].Set(val)
case PA15:
pwm.getTimer().CC[1].Set(val)
timer.CC[1].Set(val)
case PA18:
pwm.getTimer().CC[2].Set(val)
timer.CC[2].Set(val)
case PA19:
pwm.getTimer().CC[3].Set(val)
timer.CC[3].Set(val)
case PA20:
pwm.getTimer().CC[0].Set(val)
timer.CC[0].Set(val)
case PA21:
pwm.getTimer().CC[1].Set(val)
timer.CC[1].Set(val)
case PA23:
pwm.getTimer().CC[3].Set(val)
timer.CC[3].Set(val)
case PA22:
pwm.getTimer().CC[2].Set(val)
timer.CC[2].Set(val)
case PB31:
pwm.getTimer().CC[1].Set(val)
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(val uint32) {
func (pwm PWM) setChannelBuffer(timer *sam.TCC_Type, val uint32) {
switch pwm.Pin {
case PA16:
pwm.getTimer().CCBUF[0].Set(val)
timer.CCBUF[0].Set(val)
case PA17:
pwm.getTimer().CCBUF[1].Set(val)
timer.CCBUF[1].Set(val)
case PA14:
pwm.getTimer().CCBUF[0].Set(val)
timer.CCBUF[0].Set(val)
case PA15:
pwm.getTimer().CCBUF[1].Set(val)
timer.CCBUF[1].Set(val)
case PA18:
pwm.getTimer().CCBUF[2].Set(val)
timer.CCBUF[2].Set(val)
case PA19:
pwm.getTimer().CCBUF[3].Set(val)
timer.CCBUF[3].Set(val)
case PA20:
pwm.getTimer().CCBUF[0].Set(val)
timer.CCBUF[0].Set(val)
case PA21:
pwm.getTimer().CCBUF[1].Set(val)
timer.CCBUF[1].Set(val)
case PA23:
pwm.getTimer().CCBUF[3].Set(val)
timer.CCBUF[3].Set(val)
case PA22:
pwm.getTimer().CCBUF[2].Set(val)
timer.CCBUF[2].Set(val)
case PB31:
pwm.getTimer().CCBUF[1].Set(val)
timer.CCBUF[1].Set(val)
default:
return // not supported on this pin
}