mirror of
https://github.com/tinygo-org/tinygo.git
synced 2026-08-04 02:57:46 +00:00
Viable NXP/Teensy support
- Fix UART & putChar - Timer-based sleep - Enable systick in abort - Buffered, interrupt-based UART TX - Use the new interrupt API and fix sleepTicks - Make pins behave more like other boards - Use the MCU's UART numbering - Allow interrupts to wake the scheduler (#1214)
This commit is contained in:
Ethan Reesor
Ron Evans
@@ -1,5 +0,0 @@
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// +build nxp
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package runtime
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type timeUnit int64
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@@ -35,53 +35,41 @@ import (
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"device/arm"
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"device/nxp"
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"machine"
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"runtime/volatile"
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)
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const (
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WDOG_UNLOCK_SEQ1 = 0xC520
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WDOG_UNLOCK_SEQ2 = 0xD928
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watchdogUnlockSequence1 = 0xC520
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watchdogUnlockSequence2 = 0xD928
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DEFAULT_FTM_MOD = 61440 - 1
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DEFAULT_FTM_PRESCALE = 1
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_DEFAULT_FTM_MOD = 61440 - 1
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_DEFAULT_FTM_PRESCALE = 1
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)
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var (
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SIM_SOPT2_IRC48SEL = nxp.SIM_SOPT2_PLLFLLSEL(3)
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SMC_PMCTRL_HSRUN = nxp.SMC_PMCTRL_RUNM(3)
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SMC_PMSTAT_HSRUN = nxp.SMC_PMSTAT_PMSTAT(0x80)
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const (
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_SIM_SOPT2_IRC48SEL = 3 << nxp.SIM_SOPT2_PLLFLLSEL_Pos
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_SMC_PMCTRL_HSRUN = 3 << nxp.SMC_PMCTRL_RUNM_Pos
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_SMC_PMSTAT_HSRUN = 0x80 << nxp.SMC_PMSTAT_PMSTAT_Pos
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)
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var bootMsg = []byte("\r\n\r\nStartup complete, running main\r\n\r\n")
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//go:section .resetHandler
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//go:export Reset_Handler
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func main() {
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initSystem()
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arm.Asm("CPSIE i")
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initInternal()
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startupLateHook()
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initAll()
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machine.UART1.Configure(machine.UARTConfig{BaudRate: 115200})
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for _, c := range bootMsg {
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for !machine.UART1.S1.HasBits(nxp.UART_S1_TDRE) {
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}
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machine.UART1.D.Set(c)
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}
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callMain()
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run()
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abort()
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}
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// ported ResetHandler from mk20dx128.c from teensy3 core libraries
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//go:noinline
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func initSystem() {
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nxp.WDOG.UNLOCK.Set(WDOG_UNLOCK_SEQ1)
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nxp.WDOG.UNLOCK.Set(WDOG_UNLOCK_SEQ2)
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// from: ResetHandler
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nxp.WDOG.UNLOCK.Set(watchdogUnlockSequence1)
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nxp.WDOG.UNLOCK.Set(watchdogUnlockSequence2)
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arm.Asm("nop")
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arm.Asm("nop")
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startupEarlyHook()
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// TODO: hook for overriding? 'startupEarlyHook'
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nxp.WDOG.STCTRLH.Set(nxp.WDOG_STCTRLH_ALLOWUPDATE)
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// enable clocks to always-used peripherals
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nxp.SIM.SCGC3.Set(nxp.SIM_SCGC3_ADC1 | nxp.SIM_SCGC3_FTM2 | nxp.SIM_SCGC3_FTM3)
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@@ -117,9 +105,9 @@ func initSystem() {
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// enable capacitors for crystal
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nxp.OSC.CR.Set(nxp.OSC_CR_SC8P | nxp.OSC_CR_SC2P | nxp.OSC_CR_ERCLKEN)
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// enable osc, 8-32 MHz range, low power mode
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nxp.MCG.C2.Set(uint8(nxp.MCG_C2_RANGE(2) | nxp.MCG_C2_EREFS))
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nxp.MCG.C2.Set(uint8((2 << nxp.MCG_C2_RANGE_Pos) | nxp.MCG_C2_EREFS))
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// switch to crystal as clock source, FLL input = 16 MHz / 512
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nxp.MCG.C1.Set(uint8(nxp.MCG_C1_CLKS(2) | nxp.MCG_C1_FRDIV(4)))
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nxp.MCG.C1.Set(uint8((2 << nxp.MCG_C1_CLKS_Pos) | (4 << nxp.MCG_C1_FRDIV_Pos)))
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// wait for crystal oscillator to begin
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for !nxp.MCG.S.HasBits(nxp.MCG_S_OSCINIT0) {
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}
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@@ -127,7 +115,7 @@ func initSystem() {
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for nxp.MCG.S.HasBits(nxp.MCG_S_IREFST) {
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}
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// wait for MCGOUT to use oscillator
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for (nxp.MCG.S.Get() & nxp.MCG_S_CLKST_Msk) != nxp.MCG_S_CLKST(2) {
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for (nxp.MCG.S.Get() & nxp.MCG_S_CLKST_Msk) != (2 << nxp.MCG_S_CLKST_Pos) {
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}
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// now in FBE mode
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@@ -137,11 +125,11 @@ func initSystem() {
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// C6[PLLS] bit is written to 0
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// C2[LP] is written to 0
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// we need faster than the crystal, turn on the PLL (F_CPU > 120000000)
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nxp.SMC.PMCTRL.Set(SMC_PMCTRL_HSRUN) // enter HSRUN mode
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for nxp.SMC.PMSTAT.Get() != SMC_PMSTAT_HSRUN {
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nxp.SMC.PMCTRL.Set(_SMC_PMCTRL_HSRUN) // enter HSRUN mode
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for nxp.SMC.PMSTAT.Get() != _SMC_PMSTAT_HSRUN {
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} // wait for HSRUN
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nxp.MCG.C5.Set(nxp.MCG_C5_PRDIV(1))
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nxp.MCG.C6.Set(nxp.MCG_C6_PLLS | nxp.MCG_C6_VDIV(29))
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nxp.MCG.C5.Set((1 << nxp.MCG_C5_PRDIV_Pos))
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nxp.MCG.C6.Set(nxp.MCG_C6_PLLS | (29 << nxp.MCG_C6_VDIV_Pos))
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// wait for PLL to start using xtal as its input
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for !nxp.MCG.S.HasBits(nxp.MCG_S_PLLST) {
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@@ -153,18 +141,18 @@ func initSystem() {
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// now program the clock dividers
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// config divisors: 180 MHz core, 60 MHz bus, 25.7 MHz flash, USB = IRC48M
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nxp.SIM.CLKDIV1.Set(nxp.SIM_CLKDIV1_OUTDIV1(0) | nxp.SIM_CLKDIV1_OUTDIV2(2) | nxp.SIM_CLKDIV1_OUTDIV4(6))
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nxp.SIM.CLKDIV2.Set(nxp.SIM_CLKDIV2_USBDIV(0))
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nxp.SIM.CLKDIV1.Set((0 << nxp.SIM_CLKDIV1_OUTDIV1_Pos) | (2 << nxp.SIM_CLKDIV1_OUTDIV2_Pos) | (0 << nxp.SIM_CLKDIV1_OUTDIV1_Pos) | (6 << nxp.SIM_CLKDIV1_OUTDIV4_Pos))
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nxp.SIM.CLKDIV2.Set((0 << nxp.SIM_CLKDIV2_USBDIV_Pos))
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// switch to PLL as clock source, FLL input = 16 MHz / 512
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nxp.MCG.C1.Set(nxp.MCG_C1_CLKS(0) | nxp.MCG_C1_FRDIV(4))
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nxp.MCG.C1.Set((0 << nxp.MCG_C1_CLKS_Pos) | (4 << nxp.MCG_C1_FRDIV_Pos))
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// wait for PLL clock to be used
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for (nxp.MCG.S.Get() & nxp.MCG_S_CLKST_Msk) != nxp.MCG_S_CLKST(3) {
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for (nxp.MCG.S.Get() & nxp.MCG_S_CLKST_Msk) != (3 << nxp.MCG_S_CLKST_Pos) {
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}
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// now we're in PEE mode
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// trace is CPU clock, CLKOUT=OSCERCLK0
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// USB uses IRC48
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nxp.SIM.SOPT2.Set(nxp.SIM_SOPT2_USBSRC | SIM_SOPT2_IRC48SEL | nxp.SIM_SOPT2_TRACECLKSEL | nxp.SIM_SOPT2_CLKOUTSEL(6))
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nxp.SIM.SOPT2.Set(nxp.SIM_SOPT2_USBSRC | _SIM_SOPT2_IRC48SEL | nxp.SIM_SOPT2_TRACECLKSEL | (6 << nxp.SIM_SOPT2_CLKOUTSEL_Pos))
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// If the RTC oscillator isn't enabled, get it started. For Teensy 3.6
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// we don't do this early. See comment above about slow rising power.
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@@ -174,23 +162,19 @@ func initSystem() {
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}
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// initialize the SysTick counter
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nxp.SysTick.RVR.Set((machine.CPUFrequency() / 1000) - 1)
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nxp.SysTick.CVR.Set(0)
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nxp.SysTick.CSR.Set(nxp.SysTick_CSR_CLKSOURCE | nxp.SysTick_CSR_TICKINT | nxp.SysTick_CSR_ENABLE)
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nxp.SystemControl.SHPR3.Set(0x20200000) // Systick = priority 32
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initSysTick()
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}
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// ported _init_Teensyduino_internal_ from pins_teensy.c from teensy3 core libraries
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//go:noinline
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func initInternal() {
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arm.EnableIRQ(nxp.IRQ_PORTA)
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arm.EnableIRQ(nxp.IRQ_PORTB)
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arm.EnableIRQ(nxp.IRQ_PORTC)
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arm.EnableIRQ(nxp.IRQ_PORTD)
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arm.EnableIRQ(nxp.IRQ_PORTE)
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// from: _init_Teensyduino_internal_
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// arm.EnableIRQ(nxp.IRQ_PORTA)
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// arm.EnableIRQ(nxp.IRQ_PORTB)
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// arm.EnableIRQ(nxp.IRQ_PORTC)
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// arm.EnableIRQ(nxp.IRQ_PORTD)
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// arm.EnableIRQ(nxp.IRQ_PORTE)
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nxp.FTM0.CNT.Set(0)
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nxp.FTM0.MOD.Set(DEFAULT_FTM_MOD)
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nxp.FTM0.MOD.Set(_DEFAULT_FTM_MOD)
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nxp.FTM0.C0SC.Set(0x28) // MSnB:MSnA = 10, ELSnB:ELSnA = 10
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nxp.FTM0.C1SC.Set(0x28)
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nxp.FTM0.C2SC.Set(0x28)
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@@ -209,145 +193,45 @@ func initInternal() {
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nxp.FTM3.C6SC.Set(0x28)
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nxp.FTM3.C7SC.Set(0x28)
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nxp.FTM0.SC.Set(nxp.FTM_SC_CLKS(1) | nxp.FTM_SC_PS(DEFAULT_FTM_PRESCALE))
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nxp.FTM0.SC.Set((1 << nxp.FTM_SC_CLKS_Pos) | (_DEFAULT_FTM_PRESCALE << nxp.FTM_SC_PS_Pos))
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nxp.FTM1.CNT.Set(0)
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nxp.FTM1.MOD.Set(DEFAULT_FTM_MOD)
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nxp.FTM1.MOD.Set(_DEFAULT_FTM_MOD)
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nxp.FTM1.C0SC.Set(0x28)
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nxp.FTM1.C1SC.Set(0x28)
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nxp.FTM1.SC.Set(nxp.FTM_SC_CLKS(1) | nxp.FTM_SC_PS(DEFAULT_FTM_PRESCALE))
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nxp.FTM1.SC.Set((1 << nxp.FTM_SC_CLKS_Pos) | (_DEFAULT_FTM_PRESCALE << nxp.FTM_SC_PS_Pos))
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// causes a data bus error for unknown reasons
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// nxp.FTM2.CNT.Set(0)
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// nxp.FTM2.MOD.Set(DEFAULT_FTM_MOD)
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// nxp.FTM2.MOD.Set(_DEFAULT_FTM_MOD)
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// nxp.FTM2.C0SC.Set(0x28)
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// nxp.FTM2.C1SC.Set(0x28)
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// nxp.FTM2.SC.Set(nxp.FTM_SC_CLKS(1) | nxp.FTM_SC_PS(DEFAULT_FTM_PRESCALE))
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// nxp.FTM2.SC.Set((1 << nxp.FTM_SC_CLKS_Pos) | (_DEFAULT_FTM_PRESCALE << nxp.FTM_SC_PS_Pos))
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nxp.FTM3.CNT.Set(0)
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nxp.FTM3.MOD.Set(DEFAULT_FTM_MOD)
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nxp.FTM3.MOD.Set(_DEFAULT_FTM_MOD)
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nxp.FTM3.C0SC.Set(0x28)
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nxp.FTM3.C1SC.Set(0x28)
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nxp.FTM3.SC.Set(nxp.FTM_SC_CLKS(1) | nxp.FTM_SC_PS(DEFAULT_FTM_PRESCALE))
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nxp.FTM3.SC.Set((1 << nxp.FTM_SC_CLKS_Pos) | (_DEFAULT_FTM_PRESCALE << nxp.FTM_SC_PS_Pos))
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nxp.SIM.SCGC2.SetBits(nxp.SIM_SCGC2_TPM1)
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nxp.SIM.SOPT2.SetBits(nxp.SIM_SOPT2_TPMSRC(2))
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nxp.SIM.SOPT2.SetBits((2 << nxp.SIM_SOPT2_TPMSRC_Pos))
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nxp.TPM1.CNT.Set(0)
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nxp.TPM1.MOD.Set(32767)
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nxp.TPM1.C0SC.Set(0x28)
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nxp.TPM1.C1SC.Set(0x28)
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nxp.TPM1.SC.Set(nxp.FTM_SC_CLKS(1) | nxp.FTM_SC_PS(0))
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nxp.TPM1.SC.Set((1 << nxp.FTM_SC_CLKS_Pos) | (0 << nxp.FTM_SC_PS_Pos))
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// configure the low-power timer
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// nxp.LPTMR0.CSR.Set(nxp.LPTMR0_CSR_TIE)
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// nxp.LPTMR0.PSR.Set(nxp.LPTMR0_PSR_PCS(3) | nxp.LPTMR0_PSR_PRESCALE(1)) // use main (external) clock, divided by 4
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// arm.EnableIRQ(nxp.IRQ_LPTMR0)
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// configure the sleep timer
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initSleepTimer()
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// analog_init();
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// #if !defined(TEENSY_INIT_USB_DELAY_BEFORE)
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// #if TEENSYDUINO >= 142
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// #define TEENSY_INIT_USB_DELAY_BEFORE 25
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// #else
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// #define TEENSY_INIT_USB_DELAY_BEFORE 50
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// #endif
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// #endif
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// #if !defined(TEENSY_INIT_USB_DELAY_AFTER)
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// #if TEENSYDUINO >= 142
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// #define TEENSY_INIT_USB_DELAY_AFTER 275
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// #else
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// #define TEENSY_INIT_USB_DELAY_AFTER 350
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// #endif
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// #endif
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// // for background about this startup delay, please see these conversations
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// // https://forum.pjrc.com/threads/36606-startup-time-(400ms)?p=113980&viewfull=1#post113980
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// // https://forum.pjrc.com/threads/31290-Teensey-3-2-Teensey-Loader-1-24-Issues?p=87273&viewfull=1#post87273
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// delay(TEENSY_INIT_USB_DELAY_BEFORE);
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// usb_init();
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// delay(TEENSY_INIT_USB_DELAY_AFTER);
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}
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func startupEarlyHook() {
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// TODO allow override
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// > programs using the watchdog timer or needing to initialize hardware as
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// > early as possible can implement startup_early_hook()
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nxp.WDOG.STCTRLH.Set(nxp.WDOG_STCTRLH_ALLOWUPDATE)
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}
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func startupLateHook() {
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// TODO allow override
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}
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func postinit() {}
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func putchar(c byte) {
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machine.UART1.WriteByte(c)
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machine.PutcharUART(&machine.UART0, c)
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}
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// ???
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const asyncScheduler = false
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// microseconds per tick
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const tickMicros = 1000
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// number of ticks since boot
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var tickMilliCount volatile.Register32
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//go:export SysTick_Handler
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func tickHandler() {
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tickMilliCount.Set(tickMilliCount.Get() + 1)
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}
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// ticks are in microseconds
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func ticks() timeUnit {
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m := arm.DisableInterrupts()
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current := nxp.SysTick.CVR.Get()
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count := tickMilliCount.Get()
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istatus := nxp.SystemControl.ICSR.Get()
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arm.EnableInterrupts(m)
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if istatus&nxp.SystemControl_ICSR_PENDSTSET != 0 && current > 50 {
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count++
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}
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current = ((machine.CPUFrequency() / tickMicros) - 1) - current
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return timeUnit(count*tickMicros + current/(machine.CPUFrequency()/1000000))
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}
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// sleepTicks spins for a number of microseconds
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func sleepTicks(d timeUnit) {
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// TODO actually sleep
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if d <= 0 {
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return
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}
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start := ticks()
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ms := d / 1000
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for {
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for ticks()-start >= 1000 {
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ms--
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if ms <= 0 {
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return
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}
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start += 1000
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}
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arm.Asm("wfi")
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}
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}
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func Sleep(d int64) {
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sleepTicks(timeUnit(d))
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}
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// func abort() {
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// for {
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// // keep polling some communication while in fault
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// // mode, so we don't completely die.
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// if nxp.SIM.SCGC4.HasBits(nxp.SIM_SCGC4_USBOTG) usb_isr();
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// if nxp.SIM.SCGC4.HasBits(nxp.SIM_SCGC4_UART0) uart0_status_isr();
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// if nxp.SIM.SCGC4.HasBits(nxp.SIM_SCGC4_UART1) uart1_status_isr();
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// if nxp.SIM.SCGC4.HasBits(nxp.SIM_SCGC4_UART2) uart2_status_isr();
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// }
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// }
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@@ -0,0 +1,163 @@
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// Derivative work of Teensyduino Core Library
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// http://www.pjrc.com/teensy/
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// Copyright (c) 2017 PJRC.COM, LLC.
|
||||
//
|
||||
// Permission is hereby granted, free of charge, to any person obtaining
|
||||
// a copy of this software and associated documentation files (the
|
||||
// "Software"), to deal in the Software without restriction, including
|
||||
// without limitation the rights to use, copy, modify, merge, publish,
|
||||
// distribute, sublicense, and/or sell copies of the Software, and to
|
||||
// permit persons to whom the Software is furnished to do so, subject to
|
||||
// the following conditions:
|
||||
//
|
||||
// 1. The above copyright notice and this permission notice shall be
|
||||
// included in all copies or substantial portions of the Software.
|
||||
//
|
||||
// 2. If the Software is incorporated into a build system that allows
|
||||
// selection among a list of target devices, then similar target
|
||||
// devices manufactured by PJRC.COM must be included in the list of
|
||||
// target devices and selectable in the same manner.
|
||||
//
|
||||
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
|
||||
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
|
||||
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
|
||||
// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
|
||||
// BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
|
||||
// ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
|
||||
// CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
|
||||
// SOFTWARE.
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// +build nxp,mk66f18
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package runtime
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import (
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"device/arm"
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"device/nxp"
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"machine"
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"runtime/interrupt"
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"runtime/volatile"
|
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)
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||||
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type timeUnit int64
|
||||
|
||||
func ticksToNanoseconds(ticks timeUnit) int64 {
|
||||
return int64(ticks) * 1000
|
||||
}
|
||||
|
||||
func nanosecondsToTicks(ns int64) timeUnit {
|
||||
return timeUnit(ns / 1000)
|
||||
}
|
||||
|
||||
// cyclesPerMilli-1 is used for the systick reset value
|
||||
// the systick current value will be decremented on every clock cycle
|
||||
// an interrupt is generated when the current value reaches 0
|
||||
// a value of freq/1000 generates a tick (irq) every millisecond (1/1000 s)
|
||||
var cyclesPerMilli = machine.CPUFrequency() / 1000
|
||||
|
||||
// number of systick irqs (milliseconds) since boot
|
||||
var systickCount volatile.Register64
|
||||
|
||||
func millisSinceBoot() uint64 {
|
||||
return systickCount.Get()
|
||||
}
|
||||
|
||||
func initSysTick() {
|
||||
nxp.SysTick.RVR.Set(cyclesPerMilli - 1)
|
||||
nxp.SysTick.CVR.Set(0)
|
||||
nxp.SysTick.CSR.Set(nxp.SysTick_CSR_CLKSOURCE | nxp.SysTick_CSR_TICKINT | nxp.SysTick_CSR_ENABLE)
|
||||
nxp.SystemControl.SHPR3.Set((32 << nxp.SystemControl_SHPR3_PRI_15_Pos) | (32 << nxp.SystemControl_SHPR3_PRI_14_Pos)) // set systick and pendsv priority to 32
|
||||
}
|
||||
|
||||
func initSleepTimer() {
|
||||
nxp.SIM.SCGC5.SetBits(nxp.SIM_SCGC5_LPTMR)
|
||||
nxp.LPTMR0.CSR.Set(nxp.LPTMR0_CSR_TIE)
|
||||
|
||||
timerInterrupt = interrupt.New(nxp.IRQ_LPTMR0, timerWake)
|
||||
timerInterrupt.Enable()
|
||||
}
|
||||
|
||||
//go:export SysTick_Handler
|
||||
func tick() {
|
||||
systickCount.Set(systickCount.Get() + 1)
|
||||
}
|
||||
|
||||
// ticks are in microseconds
|
||||
func ticks() timeUnit {
|
||||
mask := arm.DisableInterrupts()
|
||||
current := nxp.SysTick.CVR.Get() // current value of the systick counter
|
||||
count := millisSinceBoot() // number of milliseconds since boot
|
||||
istatus := nxp.SystemControl.ICSR.Get() // interrupt status register
|
||||
arm.EnableInterrupts(mask)
|
||||
|
||||
micros := timeUnit(count * 1000) // a tick (1ms) = 1000 us
|
||||
|
||||
// if the systick counter was about to reset and ICSR indicates a pending systick irq, increment count
|
||||
if istatus&nxp.SystemControl_ICSR_PENDSTSET != 0 && current > 50 {
|
||||
micros += 1000
|
||||
} else {
|
||||
cycles := cyclesPerMilli - 1 - current // number of cycles since last 1ms tick
|
||||
cyclesPerMicro := machine.CPUFrequency() / 1000000
|
||||
micros += timeUnit(cycles / cyclesPerMicro)
|
||||
}
|
||||
|
||||
return micros
|
||||
}
|
||||
|
||||
// sleepTicks spins for a number of microseconds
|
||||
func sleepTicks(duration timeUnit) {
|
||||
now := ticks()
|
||||
end := duration + now
|
||||
cyclesPerMicro := machine.ClockFrequency() / 1000000
|
||||
|
||||
if duration <= 0 {
|
||||
return
|
||||
}
|
||||
|
||||
nxp.LPTMR0.PSR.Set((3 << nxp.LPTMR0_PSR_PCS_Pos) | nxp.LPTMR0_PSR_PBYP) // use 16MHz clock, undivided
|
||||
|
||||
for now < end {
|
||||
count := uint32(end-now) / cyclesPerMicro
|
||||
if count > 65535 {
|
||||
count = 65535
|
||||
}
|
||||
|
||||
if !timerSleep(count) {
|
||||
// return early due to interrupt
|
||||
return
|
||||
}
|
||||
|
||||
now = ticks()
|
||||
}
|
||||
}
|
||||
|
||||
var timerInterrupt interrupt.Interrupt
|
||||
var timerActive volatile.Register32
|
||||
|
||||
func timerSleep(count uint32) bool {
|
||||
timerActive.Set(1)
|
||||
nxp.LPTMR0.CMR.Set(count) // set count
|
||||
nxp.LPTMR0.CSR.SetBits(nxp.LPTMR0_CSR_TEN) // enable
|
||||
|
||||
for {
|
||||
arm.Asm("wfi")
|
||||
if timerActive.Get() == 0 {
|
||||
return true
|
||||
}
|
||||
|
||||
if hasScheduler {
|
||||
// bail out, as the interrupt may have awoken a goroutine
|
||||
break
|
||||
}
|
||||
|
||||
// if there is no scheduler, block for the entire count
|
||||
}
|
||||
|
||||
timerWake(timerInterrupt)
|
||||
return false
|
||||
}
|
||||
|
||||
func timerWake(interrupt.Interrupt) {
|
||||
timerActive.Set(0)
|
||||
nxp.LPTMR0.CSR.Set(nxp.LPTMR0.CSR.Get()&^nxp.LPTMR0_CSR_TEN | nxp.LPTMR0_CSR_TCF) // clear flag and disable
|
||||
}
|
||||
+2
-3
@@ -7,17 +7,16 @@ import "unsafe"
|
||||
const registerBase = 0x40000000
|
||||
const registerEnd = 0x40100000
|
||||
const bitbandBase = 0x42000000
|
||||
const ptrBytes = unsafe.Sizeof(uintptr(0))
|
||||
|
||||
//go:inline
|
||||
func bitbandAddress(reg uintptr, bit uint8) uintptr {
|
||||
if uintptr(bit) > ptrBytes*8 {
|
||||
if uintptr(bit) > 32 {
|
||||
panic("invalid bit position")
|
||||
}
|
||||
if reg < registerBase || reg >= registerEnd {
|
||||
panic("register is out of range")
|
||||
}
|
||||
return (reg-registerBase)*ptrBytes*8 + uintptr(bit)*ptrBytes + bitbandBase
|
||||
return (reg-registerBase)*32 + uintptr(bit)*4 + bitbandBase
|
||||
}
|
||||
|
||||
// Special types that causes loads/stores to be volatile (necessary for
|
||||
Reference in New Issue
Block a user