Mouse code for the MacroRat
Diff: mbed-dev/targets/TARGET_NXP/TARGET_LPC11U6X/serial_api.c
- Revision:
- 18:6a4db94011d3
diff -r f713758f6238 -r 6a4db94011d3 mbed-dev/targets/TARGET_NXP/TARGET_LPC11U6X/serial_api.c --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/mbed-dev/targets/TARGET_NXP/TARGET_LPC11U6X/serial_api.c Sun May 14 23:18:57 2017 +0000 @@ -0,0 +1,489 @@ +/* mbed Microcontroller Library + * Copyright (c) 2006-2013 ARM Limited + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +// math.h required for floating point operations for baud rate calculation +#include "mbed_assert.h" +#include <math.h> +#include <string.h> +#include <stdlib.h> + +#include "serial_api.h" +#include "cmsis.h" +#include "pinmap.h" + +#if DEVICE_SERIAL + +/****************************************************************************** + * INITIALIZATION + ******************************************************************************/ + +#define UART_NUM 5 + +// CFG +#define UART_EN (0x01<<0) + +// CTL +#define TXBRKEN (0x01<<1) + +// STAT +#define RXRDY (0x01<<0) +#define TXRDY (0x01<<2) +#define DELTACTS (0x01<<5) +#define RXBRK (0x01<<10) +#define DELTARXBRK (0x01<<11) + +static const PinMap PinMap_UART_TX[] = { + {P0_19, UART_0, 1}, + {P1_18, UART_0, 2}, + {P1_27, UART_0, 2}, + {P1_8 , UART_1, 2}, + {P0_14, UART_1, 4}, + {P1_0 , UART_2, 3}, + {P1_23, UART_2, 3}, + {P2_4 , UART_3, 1}, + {P2_12, UART_4, 1}, + { NC , NC , 0} +}; + +static const PinMap PinMap_UART_RX[] = { + {P0_18, UART_0, 1}, + {P1_17, UART_0, 2}, + {P1_26, UART_0, 2}, + {P1_2 , UART_1, 3}, + {P0_13, UART_1, 4}, + {P0_20, UART_2, 2}, + {P1_6 , UART_2, 2}, + {P2_3 , UART_3, 1}, + {P2_11, UART_4, 1}, + {NC , NC , 0} +}; + +static uint32_t serial_irq_ids[UART_NUM] = {0}; +static uart_irq_handler irq_handler; + +int stdio_uart_inited = 0; +serial_t stdio_uart; + +void serial_init(serial_t *obj, PinName tx, PinName rx) { + int is_stdio_uart = 0; + + // determine the UART to use + UARTName uart_tx = (UARTName)pinmap_peripheral(tx, PinMap_UART_TX); + UARTName uart_rx = (UARTName)pinmap_peripheral(rx, PinMap_UART_RX); + UARTName uart = (UARTName)pinmap_merge(uart_tx, uart_rx); + MBED_ASSERT((int)uart != NC); + + switch (uart) { + case UART_0: + obj->index = 0; + LPC_SYSCON->SYSAHBCLKCTRL |= (1 << 12); + break; + case UART_1: + obj->index = 1; + LPC_SYSCON->SYSAHBCLKCTRL |= (1 << 20); + LPC_SYSCON->PRESETCTRL |= (1 << 5); + break; + case UART_2: + obj->index = 2; + LPC_SYSCON->SYSAHBCLKCTRL |= (1 << 21); + LPC_SYSCON->PRESETCTRL |= (1 << 6); + break; + case UART_3: + obj->index = 3; + LPC_SYSCON->SYSAHBCLKCTRL |= (1 << 22); + LPC_SYSCON->PRESETCTRL |= (1 << 7); + break; + case UART_4: + obj->index = 4; + LPC_SYSCON->SYSAHBCLKCTRL |= (1 << 22); + LPC_SYSCON->PRESETCTRL |= (1 << 8); + break; + } + + if (obj->index == 0) + obj->uart = (LPC_USART0_Type *)uart; + else + obj->mini_uart = (LPC_USART4_Type *)uart; + + if (obj->index == 0) { + // enable fifos and default rx trigger level + obj->uart->FCR = 1 << 0 // FIFO Enable - 0 = Disables, 1 = Enabled + | 0 << 1 // Rx Fifo Clear + | 0 << 2 // Tx Fifo Clear + | 0 << 6; // Rx irq trigger level - 0 = 1 char, 1 = 4 chars, 2 = 8 chars, 3 = 14 chars + // disable irqs + obj->uart->IER = 0 << 0 // Rx Data available irq enable + | 0 << 1 // Tx Fifo empty irq enable + | 0 << 2; // Rx Line Status irq enable + } + else { + // Clear all status bits + obj->mini_uart->STAT = (DELTACTS | DELTARXBRK); + // Enable UART + obj->mini_uart->CFG |= UART_EN; + } + // set default baud rate and format + serial_baud (obj, 9600); + serial_format(obj, 8, ParityNone, 1); + + // pinout the chosen uart + pinmap_pinout(tx, PinMap_UART_TX); + pinmap_pinout(rx, PinMap_UART_RX); + + // set rx/tx pins in PullUp mode + if (tx != NC) { + pin_mode(tx, PullUp); + } + if (rx != NC) { + pin_mode(rx, PullUp); + } + + is_stdio_uart = (uart == STDIO_UART) ? (1) : (0); + + if (is_stdio_uart && (obj->index == 0)) { + stdio_uart_inited = 1; + memcpy(&stdio_uart, obj, sizeof(serial_t)); + } +} + +void serial_free(serial_t *obj) { + serial_irq_ids[obj->index] = 0; +} + +// serial_baud +// set the baud rate, taking in to account the current SystemFrequency +void serial_baud(serial_t *obj, int baudrate) { + LPC_SYSCON->USART0CLKDIV = 1; + LPC_SYSCON->FRGCLKDIV = 1; + + if (obj->index == 0) { + uint32_t PCLK = SystemCoreClock; + // First we check to see if the basic divide with no DivAddVal/MulVal + // ratio gives us an integer result. If it does, we set DivAddVal = 0, + // MulVal = 1. Otherwise, we search the valid ratio value range to find + // the closest match. This could be more elegant, using search methods + // and/or lookup tables, but the brute force method is not that much + // slower, and is more maintainable. + uint16_t DL = PCLK / (16 * baudrate); + + uint8_t DivAddVal = 0; + uint8_t MulVal = 1; + int hit = 0; + uint16_t dlv; + uint8_t mv, dav; + if ((PCLK % (16 * baudrate)) != 0) { // Checking for zero remainder + int err_best = baudrate, b; + for (mv = 1; mv < 16 && !hit; mv++) + { + for (dav = 0; dav < mv; dav++) + { + // baudrate = PCLK / (16 * dlv * (1 + (DivAdd / Mul)) + // solving for dlv, we get dlv = mul * PCLK / (16 * baudrate * (divadd + mul)) + // mul has 4 bits, PCLK has 27 so we have 1 bit headroom which can be used for rounding + // for many values of mul and PCLK we have 2 or more bits of headroom which can be used to improve precision + // note: X / 32 doesn't round correctly. Instead, we use ((X / 16) + 1) / 2 for correct rounding + + if ((mv * PCLK * 2) & 0x80000000) // 1 bit headroom + dlv = ((((2 * mv * PCLK) / (baudrate * (dav + mv))) / 16) + 1) / 2; + else // 2 bits headroom, use more precision + dlv = ((((4 * mv * PCLK) / (baudrate * (dav + mv))) / 32) + 1) / 2; + + // datasheet says if DLL==DLM==0, then 1 is used instead since divide by zero is ungood + if (dlv == 0) + dlv = 1; + + // datasheet says if dav > 0 then DL must be >= 2 + if ((dav > 0) && (dlv < 2)) + dlv = 2; + + // integer rearrangement of the baudrate equation (with rounding) + b = ((PCLK * mv / (dlv * (dav + mv) * 8)) + 1) / 2; + + // check to see how we went + b = abs(b - baudrate); + if (b < err_best) + { + err_best = b; + + DL = dlv; + MulVal = mv; + DivAddVal = dav; + + if (b == baudrate) + { + hit = 1; + break; + } + } + } + } + } + + // set LCR[DLAB] to enable writing to divider registers + obj->uart->LCR |= (1 << 7); + + // set divider values + obj->uart->DLM = (DL >> 8) & 0xFF; + obj->uart->DLL = (DL >> 0) & 0xFF; + obj->uart->FDR = (uint32_t) DivAddVal << 0 + | (uint32_t) MulVal << 4; + + // clear LCR[DLAB] + obj->uart->LCR &= ~(1 << 7); + } + else { + uint32_t UARTSysClk = SystemCoreClock / LPC_SYSCON->FRGCLKDIV; + obj->mini_uart->BRG = UARTSysClk / 16 / baudrate - 1; + + LPC_SYSCON->UARTFRGDIV = 0xFF; + LPC_SYSCON->UARTFRGMULT = ( ((UARTSysClk / 16) * (LPC_SYSCON->UARTFRGDIV + 1)) / + (baudrate * (obj->mini_uart->BRG + 1)) + ) - (LPC_SYSCON->UARTFRGDIV + 1); + } +} + +void serial_format(serial_t *obj, int data_bits, SerialParity parity, int stop_bits) { + MBED_ASSERT((stop_bits == 1) || (stop_bits == 2)); // 0: 1 stop bits, 1: 2 stop bits + + stop_bits -= 1; + + if (obj->index == 0) { + MBED_ASSERT((data_bits > 4) && (data_bits < 9)); // 0: 5 data bits ... 3: 8 data bits + MBED_ASSERT((parity == ParityNone) || (parity == ParityOdd) || (parity == ParityEven) || + (parity == ParityForced1) || (parity == ParityForced0)); + data_bits -= 5; + + int parity_enable, parity_select; + switch (parity) { + case ParityNone: parity_enable = 0; parity_select = 0; break; + case ParityOdd : parity_enable = 1; parity_select = 0; break; + case ParityEven: parity_enable = 1; parity_select = 1; break; + case ParityForced1: parity_enable = 1; parity_select = 2; break; + case ParityForced0: parity_enable = 1; parity_select = 3; break; + default: + return; + } + + obj->uart->LCR = data_bits << 0 + | stop_bits << 2 + | parity_enable << 3 + | parity_select << 4; + } + else { + // 0: 7 data bits ... 2: 9 data bits + MBED_ASSERT((data_bits > 6) && (data_bits < 10)); + MBED_ASSERT((parity == ParityNone) || (parity == ParityOdd) || (parity == ParityEven)); + data_bits -= 7; + + int paritysel; + switch (parity) { + case ParityNone: paritysel = 0; break; + case ParityEven: paritysel = 2; break; + case ParityOdd : paritysel = 3; break; + default: + return; + } + obj->mini_uart->CFG = (data_bits << 2) + | (paritysel << 4) + | (stop_bits << 6) + | UART_EN; + } +} + +/****************************************************************************** + * INTERRUPTS HANDLING + ******************************************************************************/ +static inline void uart_irq(uint32_t iir, uint32_t index) { + SerialIrq irq_type; + switch (iir) { + case 1: irq_type = TxIrq; break; + case 2: irq_type = RxIrq; break; + default: return; + } + + if (serial_irq_ids[index] != 0) + irq_handler(serial_irq_ids[index], irq_type); +} + +void uart0_irq() +{ + uart_irq((LPC_USART0->IIR >> 1) & 0x7, 0); +} + +void uart1_irq() +{ + if(LPC_USART1->STAT & (1 << 2)){ + uart_irq(1, 1); + } + if(LPC_USART1->STAT & (1 << 0)){ + uart_irq(2, 1); + } +} + +void uart2_irq() +{ + if(LPC_USART2->STAT & (1 << 2)){ + uart_irq(1, 2); + } + if(LPC_USART2->STAT & (1 << 0)){ + uart_irq(2, 2); + } +} + +void uart3_irq() +{ + if(LPC_USART3->STAT & (1 << 2)){ + uart_irq(1, 3); + } + if(LPC_USART3->STAT & (1 << 0)){ + uart_irq(2, 3); + } +} + +void uart4_irq() +{ + if(LPC_USART4->STAT & (1 << 2)){ + uart_irq(1, 4); + } + if(LPC_USART4->STAT & (1 << 0)){ + uart_irq(2, 4); + } +} + +void serial_irq_handler(serial_t *obj, uart_irq_handler handler, uint32_t id) { + irq_handler = handler; + serial_irq_ids[obj->index] = id; +} + +void serial_irq_set(serial_t *obj, SerialIrq irq, uint32_t enable) { + IRQn_Type irq_n = (IRQn_Type)0; + uint32_t vector = 0; + if(obj->index == 0){ + irq_n = USART0_IRQn; vector = (uint32_t)&uart0_irq; + } + else{ + switch ((int)obj->mini_uart) { + case UART_0: irq_n = USART0_IRQn; vector = (uint32_t)&uart0_irq; break; + case UART_1: irq_n = USART1_4_IRQn; vector = (uint32_t)&uart1_irq; break; + case UART_2: irq_n = USART2_3_IRQn; vector = (uint32_t)&uart2_irq; break; + case UART_3: irq_n = USART2_3_IRQn; vector = (uint32_t)&uart3_irq; break; + case UART_4: irq_n = USART1_4_IRQn; vector = (uint32_t)&uart4_irq; break; + } + } + + if (enable) { + if (obj->index == 0) { + obj->uart->IER |= (1 << irq); + } + else { + obj->mini_uart->INTENSET = (1 << ((irq == RxIrq) ? 0 : 2)); + } + NVIC_SetVector(irq_n, vector); + NVIC_EnableIRQ(irq_n); + } else { // disable + int all_disabled = 0; + SerialIrq other_irq = (irq == RxIrq) ? (RxIrq) : (TxIrq); + + if (obj->index == 0) { + obj->uart->IER &= ~(1 << irq); + all_disabled = (obj->uart->IER & (1 << other_irq)) == 0; + } + else { + obj->mini_uart->INTENCLR = (1 << ((irq == RxIrq) ? 0 : 2)); + all_disabled = (obj->mini_uart->INTENSET) == 0; + } + + if (all_disabled) + NVIC_DisableIRQ(irq_n); + } +} + +/****************************************************************************** + * READ/WRITE + ******************************************************************************/ +int serial_getc(serial_t *obj) { + while (!serial_readable(obj)); + if (obj->index == 0) { + return obj->uart->RBR; + } + else { + return obj->mini_uart->RXDAT; + } +} + +void serial_putc(serial_t *obj, int c) { + while (!serial_writable(obj)); + if (obj->index == 0) { + obj->uart->THR = c; + } + else { + obj->mini_uart->TXDAT = c; + } +} + +int serial_readable(serial_t *obj) { + if (obj->index == 0) { + return obj->uart->LSR & 0x01; + } + else { + return obj->mini_uart->STAT & RXRDY; + } +} + +int serial_writable(serial_t *obj) { + if (obj->index == 0) { + return obj->uart->LSR & 0x20; + } + else { + return obj->mini_uart->STAT & TXRDY; + } +} + +void serial_clear(serial_t *obj) { + if (obj->index == 0) { + obj->uart->FCR = 1 << 1 // rx FIFO reset + | 1 << 2 // tx FIFO reset + | 0 << 6; // interrupt depth + } + else { + obj->mini_uart->STAT = 0; + } +} + +void serial_pinout_tx(PinName tx) { + pinmap_pinout(tx, PinMap_UART_TX); +} + +void serial_break_set(serial_t *obj) { + if (obj->index == 0) { + obj->uart->LCR |= (1 << 6); + } + else { + obj->mini_uart->CTL |= TXBRKEN; + } +} + +void serial_break_clear(serial_t *obj) { + if (obj->index == 0) { + obj->uart->LCR &= ~(1 << 6); + } + else { + obj->mini_uart->CTL &= ~TXBRKEN; + } +} + + +#endif