// +build stm32l4 package machine import ( "device/stm32" "unsafe" ) // Peripheral abstraction layer for the stm32l4 const ( PA0 = portA + 0 PA1 = portA + 1 PA2 = portA + 2 PA3 = portA + 3 PA4 = portA + 4 PA5 = portA + 5 PA6 = portA + 6 PA7 = portA + 7 PA8 = portA + 8 PA9 = portA + 9 PA10 = portA + 10 PA11 = portA + 11 PA12 = portA + 12 PA13 = portA + 13 PA14 = portA + 14 PA15 = portA + 15 PB0 = portB + 0 PB1 = portB + 1 PB2 = portB + 2 PB3 = portB + 3 PB4 = portB + 4 PB5 = portB + 5 PB6 = portB + 6 PB7 = portB + 7 PB8 = portB + 8 PB9 = portB + 9 PB10 = portB + 10 PB11 = portB + 11 PB12 = portB + 12 PB13 = portB + 13 PB14 = portB + 14 PB15 = portB + 15 PC0 = portC + 0 PC1 = portC + 1 PC2 = portC + 2 PC3 = portC + 3 PC4 = portC + 4 PC5 = portC + 5 PC6 = portC + 6 PC7 = portC + 7 PC8 = portC + 8 PC9 = portC + 9 PC10 = portC + 10 PC11 = portC + 11 PC12 = portC + 12 PC13 = portC + 13 PC14 = portC + 14 PC15 = portC + 15 PD0 = portD + 0 PD1 = portD + 1 PD2 = portD + 2 PD3 = portD + 3 PD4 = portD + 4 PD5 = portD + 5 PD6 = portD + 6 PD7 = portD + 7 PD8 = portD + 8 PD9 = portD + 9 PD10 = portD + 10 PD11 = portD + 11 PD12 = portD + 12 PD13 = portD + 13 PD14 = portD + 14 PD15 = portD + 15 PE0 = portE + 0 PE1 = portE + 1 PE2 = portE + 2 PE3 = portE + 3 PE4 = portE + 4 PE5 = portE + 5 PE6 = portE + 6 PE7 = portE + 7 PE8 = portE + 8 PE9 = portE + 9 PE10 = portE + 10 PE11 = portE + 11 PE12 = portE + 12 PE13 = portE + 13 PE14 = portE + 14 PE15 = portE + 15 ) func (p Pin) getPort() *stm32.GPIO_Type { switch p / 16 { case 0: return stm32.GPIOA case 1: return stm32.GPIOB case 2: return stm32.GPIOC case 3: return stm32.GPIOD case 4: return stm32.GPIOE default: panic("machine: unknown port") } } // enableClock enables the clock for this desired GPIO port. func (p Pin) enableClock() { switch p / 16 { case 0: stm32.RCC.AHB2ENR.SetBits(stm32.RCC_AHB2ENR_GPIOAEN) case 1: stm32.RCC.AHB2ENR.SetBits(stm32.RCC_AHB2ENR_GPIOBEN) case 2: stm32.RCC.AHB2ENR.SetBits(stm32.RCC_AHB2ENR_GPIOCEN) case 3: stm32.RCC.AHB2ENR.SetBits(stm32.RCC_AHB2ENR_GPIODEN) case 4: stm32.RCC.AHB2ENR.SetBits(stm32.RCC_AHB2ENR_GPIOEEN) default: panic("machine: unknown port") } } // Enable peripheral clock func enableAltFuncClock(bus unsafe.Pointer) { switch bus { case unsafe.Pointer(stm32.PWR): // Power interface clock enable stm32.RCC.APB1ENR1.SetBits(stm32.RCC_APB1ENR1_PWREN) case unsafe.Pointer(stm32.I2C3): // I2C3 clock enable stm32.RCC.APB1ENR1.SetBits(stm32.RCC_APB1ENR1_I2C3EN) case unsafe.Pointer(stm32.I2C2): // I2C2 clock enable stm32.RCC.APB1ENR1.SetBits(stm32.RCC_APB1ENR1_I2C2EN) case unsafe.Pointer(stm32.I2C1): // I2C1 clock enable stm32.RCC.APB1ENR1.SetBits(stm32.RCC_APB1ENR1_I2C1EN) case unsafe.Pointer(stm32.UART4): // UART4 clock enable stm32.RCC.APB1ENR1.SetBits(stm32.RCC_APB1ENR1_UART4EN) case unsafe.Pointer(stm32.USART3): // USART3 clock enable stm32.RCC.APB1ENR1.SetBits(stm32.RCC_APB1ENR1_USART3EN) case unsafe.Pointer(stm32.USART2): // USART2 clock enable stm32.RCC.APB1ENR1.SetBits(stm32.RCC_APB1ENR1_USART2EN) case unsafe.Pointer(stm32.SPI3): // SPI3 clock enable stm32.RCC.APB1ENR1.SetBits(stm32.RCC_APB1ENR1_SPI3EN) case unsafe.Pointer(stm32.SPI2): // SPI2 clock enable stm32.RCC.APB1ENR1.SetBits(stm32.RCC_APB1ENR1_SPI2EN) case unsafe.Pointer(stm32.WWDG): // Window watchdog clock enable stm32.RCC.APB1ENR1.SetBits(stm32.RCC_APB1ENR1_WWDGEN) case unsafe.Pointer(stm32.TIM7): // TIM7 clock enable stm32.RCC.APB1ENR1.SetBits(stm32.RCC_APB1ENR1_TIM7EN) case unsafe.Pointer(stm32.TIM6): // TIM6 clock enable stm32.RCC.APB1ENR1.SetBits(stm32.RCC_APB1ENR1_TIM6EN) case unsafe.Pointer(stm32.TIM3): // TIM3 clock enable stm32.RCC.APB1ENR1.SetBits(stm32.RCC_APB1ENR1_TIM3EN) case unsafe.Pointer(stm32.TIM2): // TIM2 clock enable stm32.RCC.APB1ENR1.SetBits(stm32.RCC_APB1ENR1_TIM2EN) case unsafe.Pointer(stm32.LPTIM2): // LPTIM2 clock enable stm32.RCC.APB1ENR2.SetBits(stm32.RCC_APB1ENR2_LPTIM2EN) case unsafe.Pointer(stm32.I2C4): // I2C4 clock enable stm32.RCC.APB1ENR2.SetBits(stm32.RCC_APB1ENR2_I2C4EN) case unsafe.Pointer(stm32.LPUART1): // LPUART1 clock enable stm32.RCC.APB1ENR2.SetBits(stm32.RCC_APB1ENR2_LPUART1EN) case unsafe.Pointer(stm32.TIM16): // TIM16 clock enable stm32.RCC.APB2ENR.SetBits(stm32.RCC_APB2ENR_TIM16EN) case unsafe.Pointer(stm32.TIM15): // TIM15 clock enable stm32.RCC.APB2ENR.SetBits(stm32.RCC_APB2ENR_TIM15EN) case unsafe.Pointer(stm32.SYSCFG): // System configuration controller clock enable stm32.RCC.APB2ENR.SetBits(stm32.RCC_APB2ENR_SYSCFGEN) case unsafe.Pointer(stm32.SPI1): // SPI1 clock enable stm32.RCC.APB2ENR.SetBits(stm32.RCC_APB2ENR_SPI1EN) case unsafe.Pointer(stm32.USART1): // USART1 clock enable stm32.RCC.APB2ENR.SetBits(stm32.RCC_APB2ENR_USART1EN) case unsafe.Pointer(stm32.TIM1): // TIM1 clock enable stm32.RCC.APB2ENR.SetBits(stm32.RCC_APB2ENR_TIM1EN) } } //---------- SPI related types and code // SPI on the STM32Fxxx using MODER / alternate function pins type SPI struct { Bus *stm32.SPI_Type AltFuncSelector uint8 } func (spi SPI) config8Bits() { // Set rx threshold to 8-bits, so RXNE flag is set for 1 byte // (common STM32 SPI implementation does 8-bit transfers only) spi.Bus.CR2.SetBits(stm32.SPI_CR2_FRXTH) } // Set baud rate for SPI func (spi SPI) getBaudRate(config SPIConfig) uint32 { var conf uint32 // Default if config.Frequency == 0 { config.Frequency = 4e6 } localFrequency := config.Frequency // set frequency dependent on PCLK prescaler. Since these are rather weird // speeds due to the CPU freqency, pick a range up to that frquency for // clients to use more human-understandable numbers, e.g. nearest 100KHz // These are based on 80MHz peripheral clock frquency switch { case localFrequency < 312500: conf = stm32.SPI_CR1_BR_Div256 case localFrequency < 625000: conf = stm32.SPI_CR1_BR_Div128 case localFrequency < 1250000: conf = stm32.SPI_CR1_BR_Div64 case localFrequency < 2500000: conf = stm32.SPI_CR1_BR_Div32 case localFrequency < 5000000: conf = stm32.SPI_CR1_BR_Div16 case localFrequency < 10000000: conf = stm32.SPI_CR1_BR_Div8 // NOTE: many SPI components won't operate reliably (or at all) above 10MHz // Check the datasheet of the part case localFrequency < 20000000: conf = stm32.SPI_CR1_BR_Div4 case localFrequency < 40000000: conf = stm32.SPI_CR1_BR_Div2 default: // None of the specific baudrates were selected; choose the lowest speed conf = stm32.SPI_CR1_BR_Div256 } return conf << stm32.SPI_CR1_BR_Pos } // Configure SPI pins for input output and clock func (spi SPI) configurePins(config SPIConfig) { config.SCK.ConfigureAltFunc(PinConfig{Mode: PinModeSPICLK}, spi.AltFuncSelector) config.SDO.ConfigureAltFunc(PinConfig{Mode: PinModeSPISDO}, spi.AltFuncSelector) config.SDI.ConfigureAltFunc(PinConfig{Mode: PinModeSPISDI}, spi.AltFuncSelector) }