diff options
Diffstat (limited to 'esp8266/uart.c')
| -rw-r--r-- | esp8266/uart.c | 191 |
1 files changed, 191 insertions, 0 deletions
diff --git a/esp8266/uart.c b/esp8266/uart.c new file mode 100644 index 0000000000..c037b997a4 --- /dev/null +++ b/esp8266/uart.c @@ -0,0 +1,191 @@ +/****************************************************************************** + * Copyright 2013-2014 Espressif Systems (Wuxi) + * + * FileName: uart.c + * + * Description: Two UART mode configration and interrupt handler. + * Check your hardware connection while use this mode. + * + * Modification history: + * 2014/3/12, v1.0 create this file. +*******************************************************************************/ +#include "ets_sys.h" +#include "osapi.h" +#include "uart.h" +#include "osapi.h" +#include "uart_register.h" +#include "etshal.h" +#include "c_types.h" + +#define RX_BUF_SIZE (256) + +// UartDev is defined and initialized in rom code. +extern UartDevice UartDev; + +// circular buffer for RX buffering +static uint16_t rx_buf_in; +static uint16_t rx_buf_out; +static uint8_t rx_buf[RX_BUF_SIZE]; + +static void uart0_rx_intr_handler(void *para); + +/****************************************************************************** + * FunctionName : uart_config + * Description : Internal used function + * UART0 used for data TX/RX, RX buffer size is 0x100, interrupt enabled + * UART1 just used for debug output + * Parameters : uart_no, use UART0 or UART1 defined ahead + * Returns : NONE +*******************************************************************************/ +static void ICACHE_FLASH_ATTR uart_config(uint8 uart_no) { + if (uart_no == UART1) { + PIN_FUNC_SELECT(PERIPHS_IO_MUX_GPIO2_U, FUNC_U1TXD_BK); + } else { + ETS_UART_INTR_ATTACH(uart0_rx_intr_handler, NULL); + PIN_PULLUP_DIS(PERIPHS_IO_MUX_U0TXD_U); + PIN_FUNC_SELECT(PERIPHS_IO_MUX_U0TXD_U, FUNC_U0TXD); + PIN_FUNC_SELECT(PERIPHS_IO_MUX_MTDO_U, FUNC_U0RTS); + } + + uart_div_modify(uart_no, UART_CLK_FREQ / (UartDev.baut_rate)); + + WRITE_PERI_REG(UART_CONF0(uart_no), UartDev.exist_parity + | UartDev.parity + | (UartDev.stop_bits << UART_STOP_BIT_NUM_S) + | (UartDev.data_bits << UART_BIT_NUM_S)); + + // clear rx and tx fifo,not ready + SET_PERI_REG_MASK(UART_CONF0(uart_no), UART_RXFIFO_RST | UART_TXFIFO_RST); + CLEAR_PERI_REG_MASK(UART_CONF0(uart_no), UART_RXFIFO_RST | UART_TXFIFO_RST); + + if (uart_no == UART0) { + // set rx fifo trigger + WRITE_PERI_REG(UART_CONF1(uart_no), + ((0x10 & UART_RXFIFO_FULL_THRHD) << UART_RXFIFO_FULL_THRHD_S) | + ((0x10 & UART_RX_FLOW_THRHD) << UART_RX_FLOW_THRHD_S) | + UART_RX_FLOW_EN | + (0x02 & UART_RX_TOUT_THRHD) << UART_RX_TOUT_THRHD_S | + UART_RX_TOUT_EN); + SET_PERI_REG_MASK(UART_INT_ENA(uart_no), UART_RXFIFO_TOUT_INT_ENA | + UART_FRM_ERR_INT_ENA); + } else { + WRITE_PERI_REG(UART_CONF1(uart_no), + ((UartDev.rcv_buff.TrigLvl & UART_RXFIFO_FULL_THRHD) << UART_RXFIFO_FULL_THRHD_S)); + } + + // clear all interrupt + WRITE_PERI_REG(UART_INT_CLR(uart_no), 0xffff); + // enable rx_interrupt + SET_PERI_REG_MASK(UART_INT_ENA(uart_no), UART_RXFIFO_FULL_INT_ENA); + + // init RX buffer + rx_buf_in = 0; + rx_buf_out = 0; +} + +/****************************************************************************** + * FunctionName : uart1_tx_one_char + * Description : Internal used function + * Use uart1 interface to transfer one char + * Parameters : uint8 TxChar - character to tx + * Returns : OK +*******************************************************************************/ +void uart_tx_one_char(uint8 uart, uint8 TxChar) { + while (true) { + uint32 fifo_cnt = READ_PERI_REG(UART_STATUS(uart)) & (UART_TXFIFO_CNT<<UART_TXFIFO_CNT_S); + if ((fifo_cnt >> UART_TXFIFO_CNT_S & UART_TXFIFO_CNT) < 126) { + break; + } + } + WRITE_PERI_REG(UART_FIFO(uart), TxChar); +} + +/****************************************************************************** + * FunctionName : uart1_write_char + * Description : Internal used function + * Do some special deal while tx char is '\r' or '\n' + * Parameters : char c - character to tx + * Returns : NONE +*******************************************************************************/ +static void ICACHE_FLASH_ATTR +uart1_write_char(char c) { + if (c == '\n') { + uart_tx_one_char(UART1, '\r'); + uart_tx_one_char(UART1, '\n'); + } else if (c == '\r') { + } else { + uart_tx_one_char(UART1, c); + } +} + +/****************************************************************************** + * FunctionName : uart0_rx_intr_handler + * Description : Internal used function + * UART0 interrupt handler, add self handle code inside + * Parameters : void *para - point to ETS_UART_INTR_ATTACH's arg + * Returns : NONE +*******************************************************************************/ + +static void uart0_rx_intr_handler(void *para) { + /* uart0 and uart1 intr combine togther, when interrupt occur, see reg 0x3ff20020, bit2, bit0 represents + * uart1 and uart0 respectively + */ + + uint8 RcvChar; + uint8 uart_no = UART0; + + if (UART_FRM_ERR_INT_ST == (READ_PERI_REG(UART_INT_ST(uart_no)) & UART_FRM_ERR_INT_ST)) { + // frame error + WRITE_PERI_REG(UART_INT_CLR(uart_no), UART_FRM_ERR_INT_CLR); + } + + if (UART_RXFIFO_FULL_INT_ST == (READ_PERI_REG(UART_INT_ST(uart_no)) & UART_RXFIFO_FULL_INT_ST)) { + // fifo full + WRITE_PERI_REG(UART_INT_CLR(uart_no), UART_RXFIFO_FULL_INT_CLR); + goto read_chars; + } else if (UART_RXFIFO_TOUT_INT_ST == (READ_PERI_REG(UART_INT_ST(uart_no)) & UART_RXFIFO_TOUT_INT_ST)) { + WRITE_PERI_REG(UART_INT_CLR(uart_no), UART_RXFIFO_TOUT_INT_CLR); + read_chars: + while (READ_PERI_REG(UART_STATUS(uart_no)) & (UART_RXFIFO_CNT << UART_RXFIFO_CNT_S)) { + RcvChar = READ_PERI_REG(UART_FIFO(uart_no)) & 0xff; + uint16_t rx_buf_in_next = (rx_buf_in + 1) % RX_BUF_SIZE; + if (rx_buf_in_next != rx_buf_out) { + rx_buf[rx_buf_in] = RcvChar; + rx_buf_in = rx_buf_in_next; + } + } + } +} + +int uart0_rx(void) { + if (rx_buf_out != rx_buf_in) { + int chr = rx_buf[rx_buf_out]; + rx_buf_out = (rx_buf_out + 1) % RX_BUF_SIZE; + return chr; + } else { + return -1; + } +} + +/****************************************************************************** + * FunctionName : uart_init + * Description : user interface for init uart + * Parameters : UartBautRate uart0_br - uart0 bautrate + * UartBautRate uart1_br - uart1 bautrate + * Returns : NONE +*******************************************************************************/ +void ICACHE_FLASH_ATTR uart_init(UartBautRate uart0_br, UartBautRate uart1_br) { + // rom use 74880 baut_rate, here reinitialize + UartDev.baut_rate = uart0_br; + uart_config(UART0); + UartDev.baut_rate = uart1_br; + uart_config(UART1); + ETS_UART_INTR_ENABLE(); + + // install uart1 putc callback + os_install_putc1((void *)uart1_write_char); +} + +void ICACHE_FLASH_ATTR uart_reattach() { + uart_init(UART_BIT_RATE_74880, UART_BIT_RATE_74880); +} |