circuitpython/cc3200/mods/pybuart.c

672 lines
23 KiB
C

/*
* This file is part of the MicroPython project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2013, 2014 Damien P. George
* Copyright (c) 2015 Daniel Campora
*
* 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:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* 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.
*/
#include <stdint.h>
#include <stdio.h>
#include <string.h>
#include "py/mpconfig.h"
#include "py/obj.h"
#include "py/runtime.h"
#include "py/objlist.h"
#include "py/stream.h"
#include "py/mphal.h"
#include "inc/hw_types.h"
#include "inc/hw_ints.h"
#include "inc/hw_memmap.h"
#include "inc/hw_uart.h"
#include "rom_map.h"
#include "interrupt.h"
#include "prcm.h"
#include "uart.h"
#include "pybuart.h"
#include "mpirq.h"
#include "pybsleep.h"
#include "mpexception.h"
#include "py/mpstate.h"
#include "osi.h"
#include "utils.h"
#include "pin.h"
#include "pybpin.h"
#include "pins.h"
#include "moduos.h"
/// \moduleref pyb
/// \class UART - duplex serial communication bus
/******************************************************************************
DEFINE CONSTANTS
*******-***********************************************************************/
#define PYBUART_FRAME_TIME_US(baud) ((11 * 1000000) / baud)
#define PYBUART_2_FRAMES_TIME_US(baud) (PYBUART_FRAME_TIME_US(baud) * 2)
#define PYBUART_RX_TIMEOUT_US(baud) (PYBUART_2_FRAMES_TIME_US(baud) * 8) // we need at least characters in the FIFO
#define PYBUART_TX_WAIT_US(baud) ((PYBUART_FRAME_TIME_US(baud)) + 1)
#define PYBUART_TX_MAX_TIMEOUT_MS (5)
#define PYBUART_RX_BUFFER_LEN (256)
// interrupt triggers
#define UART_TRIGGER_RX_ANY (0x01)
#define UART_TRIGGER_RX_HALF (0x02)
#define UART_TRIGGER_RX_FULL (0x04)
#define UART_TRIGGER_TX_DONE (0x08)
/******************************************************************************
DECLARE PRIVATE FUNCTIONS
******************************************************************************/
STATIC void uart_init (pyb_uart_obj_t *self);
STATIC bool uart_rx_wait (pyb_uart_obj_t *self);
STATIC void uart_check_init(pyb_uart_obj_t *self);
STATIC mp_obj_t uart_irq_new (pyb_uart_obj_t *self, byte trigger, mp_int_t priority, mp_obj_t handler);
STATIC void UARTGenericIntHandler(uint32_t uart_id);
STATIC void UART0IntHandler(void);
STATIC void UART1IntHandler(void);
STATIC void uart_irq_enable (mp_obj_t self_in);
STATIC void uart_irq_disable (mp_obj_t self_in);
/******************************************************************************
DEFINE PRIVATE TYPES
******************************************************************************/
struct _pyb_uart_obj_t {
mp_obj_base_t base;
pyb_uart_id_t uart_id;
uint reg;
uint baudrate;
uint config;
uint flowcontrol;
byte *read_buf; // read buffer pointer
volatile uint16_t read_buf_head; // indexes first empty slot
uint16_t read_buf_tail; // indexes first full slot (not full if equals head)
byte peripheral;
byte irq_trigger;
bool irq_enabled;
byte irq_flags;
};
/******************************************************************************
DECLARE PRIVATE DATA
******************************************************************************/
STATIC pyb_uart_obj_t pyb_uart_obj[PYB_NUM_UARTS] = { {.reg = UARTA0_BASE, .baudrate = 0, .read_buf = NULL, .peripheral = PRCM_UARTA0},
{.reg = UARTA1_BASE, .baudrate = 0, .read_buf = NULL, .peripheral = PRCM_UARTA1} };
STATIC const mp_irq_methods_t uart_irq_methods;
STATIC const mp_obj_t pyb_uart_def_pin[PYB_NUM_UARTS][2] = { {&pin_GP1, &pin_GP2}, {&pin_GP3, &pin_GP4} };
/******************************************************************************
DEFINE PUBLIC FUNCTIONS
******************************************************************************/
void uart_init0 (void) {
// save references of the UART objects, to prevent the read buffers from being trashed by the gc
MP_STATE_PORT(pyb_uart_objs)[0] = &pyb_uart_obj[0];
MP_STATE_PORT(pyb_uart_objs)[1] = &pyb_uart_obj[1];
}
uint32_t uart_rx_any(pyb_uart_obj_t *self) {
if (self->read_buf_tail != self->read_buf_head) {
// buffering via irq
return (self->read_buf_head > self->read_buf_tail) ? self->read_buf_head - self->read_buf_tail :
PYBUART_RX_BUFFER_LEN - self->read_buf_tail + self->read_buf_head;
}
return MAP_UARTCharsAvail(self->reg) ? 1 : 0;
}
int uart_rx_char(pyb_uart_obj_t *self) {
if (self->read_buf_tail != self->read_buf_head) {
// buffering via irq
int data = self->read_buf[self->read_buf_tail];
self->read_buf_tail = (self->read_buf_tail + 1) % PYBUART_RX_BUFFER_LEN;
return data;
} else {
// no buffering
return MAP_UARTCharGetNonBlocking(self->reg);
}
}
bool uart_tx_char(pyb_uart_obj_t *self, int c) {
uint32_t timeout = 0;
while (!MAP_UARTCharPutNonBlocking(self->reg, c)) {
if (timeout++ > ((PYBUART_TX_MAX_TIMEOUT_MS * 1000) / PYBUART_TX_WAIT_US(self->baudrate))) {
return false;
}
UtilsDelay(UTILS_DELAY_US_TO_COUNT(PYBUART_TX_WAIT_US(self->baudrate)));
}
return true;
}
bool uart_tx_strn(pyb_uart_obj_t *self, const char *str, uint len) {
for (const char *top = str + len; str < top; str++) {
if (!uart_tx_char(self, *str)) {
return false;
}
}
return true;
}
/******************************************************************************
DEFINE PRIVATE FUNCTIONS
******************************************************************************/
// assumes init parameters have been set up correctly
STATIC void uart_init (pyb_uart_obj_t *self) {
// Enable the peripheral clock
MAP_PRCMPeripheralClkEnable(self->peripheral, PRCM_RUN_MODE_CLK | PRCM_SLP_MODE_CLK);
// Reset the uart
MAP_PRCMPeripheralReset(self->peripheral);
// re-allocate the read buffer after resetting the uart (which automatically disables any irqs)
self->read_buf_head = 0;
self->read_buf_tail = 0;
self->read_buf = MP_OBJ_NULL; // free the read buffer before allocating again
self->read_buf = m_new(byte, PYBUART_RX_BUFFER_LEN);
// Initialize the UART
MAP_UARTConfigSetExpClk(self->reg, MAP_PRCMPeripheralClockGet(self->peripheral),
self->baudrate, self->config);
// Enable the FIFO
MAP_UARTFIFOEnable(self->reg);
// Configure the FIFO interrupt levels
MAP_UARTFIFOLevelSet(self->reg, UART_FIFO_TX4_8, UART_FIFO_RX4_8);
// Configure the flow control mode
UARTFlowControlSet(self->reg, self->flowcontrol);
}
// Waits at most timeout microseconds for at least 1 char to become ready for
// reading (from buf or for direct reading).
// Returns true if something available, false if not.
STATIC bool uart_rx_wait (pyb_uart_obj_t *self) {
int timeout = PYBUART_RX_TIMEOUT_US(self->baudrate);
for ( ; ; ) {
if (uart_rx_any(self)) {
return true; // we have at least 1 char ready for reading
}
if (timeout > 0) {
UtilsDelay(UTILS_DELAY_US_TO_COUNT(1));
timeout--;
}
else {
return false;
}
}
}
STATIC mp_obj_t uart_irq_new (pyb_uart_obj_t *self, byte trigger, mp_int_t priority, mp_obj_t handler) {
// disable the uart interrupts before updating anything
uart_irq_disable (self);
if (self->uart_id == PYB_UART_0) {
MAP_IntPrioritySet(INT_UARTA0, priority);
MAP_UARTIntRegister(self->reg, UART0IntHandler);
} else {
MAP_IntPrioritySet(INT_UARTA1, priority);
MAP_UARTIntRegister(self->reg, UART1IntHandler);
}
// create the callback
mp_obj_t _irq = mp_irq_new ((mp_obj_t)self, handler, &uart_irq_methods);
// enable the interrupts now
self->irq_trigger = trigger;
uart_irq_enable (self);
return _irq;
}
STATIC void UARTGenericIntHandler(uint32_t uart_id) {
pyb_uart_obj_t *self;
uint32_t status;
self = &pyb_uart_obj[uart_id];
status = MAP_UARTIntStatus(self->reg, true);
// receive interrupt
if (status & (UART_INT_RX | UART_INT_RT)) {
// set the flags
self->irq_flags = UART_TRIGGER_RX_ANY;
MAP_UARTIntClear(self->reg, UART_INT_RX | UART_INT_RT);
while (UARTCharsAvail(self->reg)) {
int data = MAP_UARTCharGetNonBlocking(self->reg);
if (MP_STATE_PORT(os_term_dup_obj) && MP_STATE_PORT(os_term_dup_obj)->stream_o == self && data == user_interrupt_char) {
// raise an exception when interrupts are finished
mpexception_keyboard_nlr_jump();
} else { // there's always a read buffer available
uint16_t next_head = (self->read_buf_head + 1) % PYBUART_RX_BUFFER_LEN;
if (next_head != self->read_buf_tail) {
// only store data if room in buf
self->read_buf[self->read_buf_head] = data;
self->read_buf_head = next_head;
}
}
}
}
// check the flags to see if the user handler should be called
if ((self->irq_trigger & self->irq_flags) && self->irq_enabled) {
// call the user defined handler
mp_irq_handler(mp_irq_find(self));
}
// clear the flags
self->irq_flags = 0;
}
STATIC void uart_check_init(pyb_uart_obj_t *self) {
// not initialized
if (!self->baudrate) {
mp_raise_OSError(MP_EPERM);
}
}
STATIC void UART0IntHandler(void) {
UARTGenericIntHandler(0);
}
STATIC void UART1IntHandler(void) {
UARTGenericIntHandler(1);
}
STATIC void uart_irq_enable (mp_obj_t self_in) {
pyb_uart_obj_t *self = self_in;
// check for any of the rx interrupt types
if (self->irq_trigger & (UART_TRIGGER_RX_ANY | UART_TRIGGER_RX_HALF | UART_TRIGGER_RX_FULL)) {
MAP_UARTIntClear(self->reg, UART_INT_RX | UART_INT_RT);
MAP_UARTIntEnable(self->reg, UART_INT_RX | UART_INT_RT);
}
self->irq_enabled = true;
}
STATIC void uart_irq_disable (mp_obj_t self_in) {
pyb_uart_obj_t *self = self_in;
self->irq_enabled = false;
}
STATIC int uart_irq_flags (mp_obj_t self_in) {
pyb_uart_obj_t *self = self_in;
return self->irq_flags;
}
/******************************************************************************/
/* MicroPython bindings */
STATIC void pyb_uart_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t kind) {
pyb_uart_obj_t *self = self_in;
if (self->baudrate > 0) {
mp_printf(print, "UART(%u, baudrate=%u, bits=", self->uart_id, self->baudrate);
switch (self->config & UART_CONFIG_WLEN_MASK) {
case UART_CONFIG_WLEN_5:
mp_print_str(print, "5");
break;
case UART_CONFIG_WLEN_6:
mp_print_str(print, "6");
break;
case UART_CONFIG_WLEN_7:
mp_print_str(print, "7");
break;
case UART_CONFIG_WLEN_8:
mp_print_str(print, "8");
break;
default:
break;
}
if ((self->config & UART_CONFIG_PAR_MASK) == UART_CONFIG_PAR_NONE) {
mp_print_str(print, ", parity=None");
} else {
mp_printf(print, ", parity=UART.%q", (self->config & UART_CONFIG_PAR_MASK) == UART_CONFIG_PAR_EVEN ? MP_QSTR_EVEN : MP_QSTR_ODD);
}
mp_printf(print, ", stop=%u)", (self->config & UART_CONFIG_STOP_MASK) == UART_CONFIG_STOP_ONE ? 1 : 2);
}
else {
mp_printf(print, "UART(%u)", self->uart_id);
}
}
STATIC mp_obj_t pyb_uart_init_helper(pyb_uart_obj_t *self, const mp_arg_val_t *args) {
// get the baudrate
if (args[0].u_int <= 0) {
goto error;
}
uint baudrate = args[0].u_int;
uint config;
switch (args[1].u_int) {
case 5:
config = UART_CONFIG_WLEN_5;
break;
case 6:
config = UART_CONFIG_WLEN_6;
break;
case 7:
config = UART_CONFIG_WLEN_7;
break;
case 8:
config = UART_CONFIG_WLEN_8;
break;
default:
goto error;
break;
}
// parity
if (args[2].u_obj == mp_const_none) {
config |= UART_CONFIG_PAR_NONE;
} else {
uint parity = mp_obj_get_int(args[2].u_obj);
if (parity == 0) {
config |= UART_CONFIG_PAR_EVEN;
} else if (parity == 1) {
config |= UART_CONFIG_PAR_ODD;
} else {
goto error;
}
}
// stop bits
config |= (args[3].u_int == 1 ? UART_CONFIG_STOP_ONE : UART_CONFIG_STOP_TWO);
// assign the pins
mp_obj_t pins_o = args[4].u_obj;
uint flowcontrol = UART_FLOWCONTROL_NONE;
if (pins_o != mp_const_none) {
mp_obj_t *pins;
size_t n_pins = 2;
if (pins_o == MP_OBJ_NULL) {
// use the default pins
pins = (mp_obj_t *)pyb_uart_def_pin[self->uart_id];
} else {
mp_obj_get_array(pins_o, &n_pins, &pins);
if (n_pins != 2 && n_pins != 4) {
goto error;
}
if (n_pins == 4) {
if (pins[PIN_TYPE_UART_RTS] != mp_const_none && pins[PIN_TYPE_UART_RX] == mp_const_none) {
goto error; // RTS pin given in TX only mode
} else if (pins[PIN_TYPE_UART_CTS] != mp_const_none && pins[PIN_TYPE_UART_TX] == mp_const_none) {
goto error; // CTS pin given in RX only mode
} else {
if (pins[PIN_TYPE_UART_RTS] != mp_const_none) {
flowcontrol |= UART_FLOWCONTROL_RX;
}
if (pins[PIN_TYPE_UART_CTS] != mp_const_none) {
flowcontrol |= UART_FLOWCONTROL_TX;
}
}
}
}
pin_assign_pins_af (pins, n_pins, PIN_TYPE_STD_PU, PIN_FN_UART, self->uart_id);
}
self->baudrate = baudrate;
self->config = config;
self->flowcontrol = flowcontrol;
// initialize and enable the uart
uart_init (self);
// register it with the sleep module
pyb_sleep_add ((const mp_obj_t)self, (WakeUpCB_t)uart_init);
// enable the callback
uart_irq_new (self, UART_TRIGGER_RX_ANY, INT_PRIORITY_LVL_3, mp_const_none);
// disable the irq (from the user point of view)
uart_irq_disable(self);
return mp_const_none;
error:
mp_raise_ValueError(mpexception_value_invalid_arguments);
}
STATIC const mp_arg_t pyb_uart_init_args[] = {
{ MP_QSTR_id, MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
{ MP_QSTR_baudrate, MP_ARG_INT, {.u_int = 9600} },
{ MP_QSTR_bits, MP_ARG_INT, {.u_int = 8} },
{ MP_QSTR_parity, MP_ARG_OBJ, {.u_obj = mp_const_none} },
{ MP_QSTR_stop, MP_ARG_INT, {.u_int = 1} },
{ MP_QSTR_pins, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
};
STATIC mp_obj_t pyb_uart_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *all_args) {
// parse args
mp_map_t kw_args;
mp_map_init_fixed_table(&kw_args, n_kw, all_args + n_args);
mp_arg_val_t args[MP_ARRAY_SIZE(pyb_uart_init_args)];
mp_arg_parse_all(n_args, all_args, &kw_args, MP_ARRAY_SIZE(args), pyb_uart_init_args, args);
// work out the uart id
uint uart_id;
if (args[0].u_obj == MP_OBJ_NULL) {
if (args[5].u_obj != MP_OBJ_NULL) {
mp_obj_t *pins;
size_t n_pins = 2;
mp_obj_get_array(args[5].u_obj, &n_pins, &pins);
// check the Tx pin (or the Rx if Tx is None)
if (pins[0] == mp_const_none) {
uart_id = pin_find_peripheral_unit(pins[1], PIN_FN_UART, PIN_TYPE_UART_RX);
} else {
uart_id = pin_find_peripheral_unit(pins[0], PIN_FN_UART, PIN_TYPE_UART_TX);
}
} else {
// default id
uart_id = 0;
}
} else {
uart_id = mp_obj_get_int(args[0].u_obj);
}
if (uart_id > PYB_UART_1) {
mp_raise_OSError(MP_ENODEV);
}
// get the correct uart instance
pyb_uart_obj_t *self = &pyb_uart_obj[uart_id];
self->base.type = &pyb_uart_type;
self->uart_id = uart_id;
// start the peripheral
pyb_uart_init_helper(self, &args[1]);
return self;
}
STATIC mp_obj_t pyb_uart_init(mp_uint_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
// parse args
mp_arg_val_t args[MP_ARRAY_SIZE(pyb_uart_init_args) - 1];
mp_arg_parse_all(n_args - 1, pos_args + 1, kw_args, MP_ARRAY_SIZE(args), &pyb_uart_init_args[1], args);
return pyb_uart_init_helper(pos_args[0], args);
}
STATIC MP_DEFINE_CONST_FUN_OBJ_KW(pyb_uart_init_obj, 1, pyb_uart_init);
STATIC mp_obj_t pyb_uart_deinit(mp_obj_t self_in) {
pyb_uart_obj_t *self = self_in;
// unregister it with the sleep module
pyb_sleep_remove (self);
// invalidate the baudrate
self->baudrate = 0;
// free the read buffer
m_del(byte, self->read_buf, PYBUART_RX_BUFFER_LEN);
MAP_UARTIntDisable(self->reg, UART_INT_RX | UART_INT_RT);
MAP_UARTDisable(self->reg);
MAP_PRCMPeripheralClkDisable(self->peripheral, PRCM_RUN_MODE_CLK | PRCM_SLP_MODE_CLK);
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(pyb_uart_deinit_obj, pyb_uart_deinit);
STATIC mp_obj_t pyb_uart_any(mp_obj_t self_in) {
pyb_uart_obj_t *self = self_in;
uart_check_init(self);
return mp_obj_new_int(uart_rx_any(self));
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(pyb_uart_any_obj, pyb_uart_any);
STATIC mp_obj_t pyb_uart_sendbreak(mp_obj_t self_in) {
pyb_uart_obj_t *self = self_in;
uart_check_init(self);
// send a break signal for at least 2 complete frames
MAP_UARTBreakCtl(self->reg, true);
UtilsDelay(UTILS_DELAY_US_TO_COUNT(PYBUART_2_FRAMES_TIME_US(self->baudrate)));
MAP_UARTBreakCtl(self->reg, false);
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(pyb_uart_sendbreak_obj, pyb_uart_sendbreak);
/// \method irq(trigger, priority, handler, wake)
STATIC mp_obj_t pyb_uart_irq (mp_uint_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
mp_arg_val_t args[mp_irq_INIT_NUM_ARGS];
mp_arg_parse_all(n_args - 1, pos_args + 1, kw_args, mp_irq_INIT_NUM_ARGS, mp_irq_init_args, args);
// check if any parameters were passed
pyb_uart_obj_t *self = pos_args[0];
uart_check_init(self);
// convert the priority to the correct value
uint priority = mp_irq_translate_priority (args[1].u_int);
// check the power mode
uint8_t pwrmode = (args[3].u_obj == mp_const_none) ? PYB_PWR_MODE_ACTIVE : mp_obj_get_int(args[3].u_obj);
if (PYB_PWR_MODE_ACTIVE != pwrmode) {
goto invalid_args;
}
// check the trigger
uint trigger = mp_obj_get_int(args[0].u_obj);
if (!trigger || trigger > (UART_TRIGGER_RX_ANY | UART_TRIGGER_RX_HALF | UART_TRIGGER_RX_FULL | UART_TRIGGER_TX_DONE)) {
goto invalid_args;
}
// register a new callback
return uart_irq_new (self, trigger, priority, args[2].u_obj);
invalid_args:
mp_raise_ValueError(mpexception_value_invalid_arguments);
}
STATIC MP_DEFINE_CONST_FUN_OBJ_KW(pyb_uart_irq_obj, 1, pyb_uart_irq);
STATIC const mp_rom_map_elem_t pyb_uart_locals_dict_table[] = {
// instance methods
{ MP_ROM_QSTR(MP_QSTR_init), MP_ROM_PTR(&pyb_uart_init_obj) },
{ MP_ROM_QSTR(MP_QSTR_deinit), MP_ROM_PTR(&pyb_uart_deinit_obj) },
{ MP_ROM_QSTR(MP_QSTR_any), MP_ROM_PTR(&pyb_uart_any_obj) },
{ MP_ROM_QSTR(MP_QSTR_sendbreak), MP_ROM_PTR(&pyb_uart_sendbreak_obj) },
{ MP_ROM_QSTR(MP_QSTR_irq), MP_ROM_PTR(&pyb_uart_irq_obj) },
/// \method read([nbytes])
{ MP_ROM_QSTR(MP_QSTR_read), MP_ROM_PTR(&mp_stream_read_obj) },
/// \method readline()
{ MP_ROM_QSTR(MP_QSTR_readline), MP_ROM_PTR(&mp_stream_unbuffered_readline_obj) },
/// \method readinto(buf[, nbytes])
{ MP_ROM_QSTR(MP_QSTR_readinto), MP_ROM_PTR(&mp_stream_readinto_obj) },
/// \method write(buf)
{ MP_ROM_QSTR(MP_QSTR_write), MP_ROM_PTR(&mp_stream_write_obj) },
// class constants
{ MP_ROM_QSTR(MP_QSTR_RX_ANY), MP_ROM_INT(UART_TRIGGER_RX_ANY) },
};
STATIC MP_DEFINE_CONST_DICT(pyb_uart_locals_dict, pyb_uart_locals_dict_table);
STATIC mp_uint_t pyb_uart_read(mp_obj_t self_in, void *buf_in, mp_uint_t size, int *errcode) {
pyb_uart_obj_t *self = self_in;
byte *buf = buf_in;
uart_check_init(self);
// make sure we want at least 1 char
if (size == 0) {
return 0;
}
// wait for first char to become available
if (!uart_rx_wait(self)) {
// return MP_EAGAIN error to indicate non-blocking (then read() method returns None)
*errcode = MP_EAGAIN;
return MP_STREAM_ERROR;
}
// read the data
byte *orig_buf = buf;
for ( ; ; ) {
*buf++ = uart_rx_char(self);
if (--size == 0 || !uart_rx_wait(self)) {
// return number of bytes read
return buf - orig_buf;
}
}
}
STATIC mp_uint_t pyb_uart_write(mp_obj_t self_in, const void *buf_in, mp_uint_t size, int *errcode) {
pyb_uart_obj_t *self = self_in;
const char *buf = buf_in;
uart_check_init(self);
// write the data
if (!uart_tx_strn(self, buf, size)) {
mp_raise_OSError(MP_EIO);
}
return size;
}
STATIC mp_uint_t pyb_uart_ioctl(mp_obj_t self_in, mp_uint_t request, mp_uint_t arg, int *errcode) {
pyb_uart_obj_t *self = self_in;
mp_uint_t ret;
uart_check_init(self);
if (request == MP_STREAM_POLL) {
mp_uint_t flags = arg;
ret = 0;
if ((flags & MP_STREAM_POLL_RD) && uart_rx_any(self)) {
ret |= MP_STREAM_POLL_RD;
}
if ((flags & MP_STREAM_POLL_WR) && MAP_UARTSpaceAvail(self->reg)) {
ret |= MP_STREAM_POLL_WR;
}
} else {
*errcode = MP_EINVAL;
ret = MP_STREAM_ERROR;
}
return ret;
}
STATIC const mp_stream_p_t uart_stream_p = {
.read = pyb_uart_read,
.write = pyb_uart_write,
.ioctl = pyb_uart_ioctl,
.is_text = false,
};
STATIC const mp_irq_methods_t uart_irq_methods = {
.init = pyb_uart_irq,
.enable = uart_irq_enable,
.disable = uart_irq_disable,
.flags = uart_irq_flags
};
const mp_obj_type_t pyb_uart_type = {
{ &mp_type_type },
.name = MP_QSTR_UART,
.print = pyb_uart_print,
.make_new = pyb_uart_make_new,
.getiter = mp_identity_getiter,
.iternext = mp_stream_unbuffered_iter,
.protocol = &uart_stream_p,
.locals_dict = (mp_obj_t)&pyb_uart_locals_dict,
};