ports: Make new ports/ sub-directory and move all ports there.

This is to keep the top-level directory clean, to make it clear what is
core and what is a port, and to allow the repository to grow with new ports
in a sustainable way.

1 files changed, 0 insertions, 901 deletions

diff --git a/stmhal/can.c b/stmhal/can.c
deleted file mode 100644
index 2fd593d58..000000000
--- a/stmhal/can.c
+++ /dev/null
@@ -1,901 +0,0 @@
-/*
- * This file is part of the MicroPython project, http://micropython.org/
- *
- * The MIT License (MIT)
- *
- * Copyright (c) 2014 Damien P. George
- *
- * 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 <stdio.h>
-#include <string.h>
-#include <stdarg.h>
-
-#include "py/nlr.h"
-#include "py/objtuple.h"
-#include "py/runtime.h"
-#include "py/gc.h"
-#include "py/stream.h"
-#include "py/mperrno.h"
-#include "py/mphal.h"
-#include "bufhelper.h"
-#include "can.h"
-#include "irq.h"
-
-#if MICROPY_HW_ENABLE_CAN
-
-#define MASK16 (0)
-#define LIST16 (1)
-#define MASK32 (2)
-#define LIST32 (3)
-
-/// \moduleref pyb
-/// \class CAN - controller area network communication bus
-///
-/// CAN implements the standard CAN communications protocol.  At
-/// the physical level it consists of 2 lines: RX and TX.  Note that
-/// to connect the pyboard to a CAN bus you must use a CAN transceiver
-/// to convert the CAN logic signals from the pyboard to the correct
-/// voltage levels on the bus.
-///
-/// Note that this driver does not yet support filter configuration
-/// (it defaults to a single filter that lets through all messages),
-/// or bus timing configuration (except for setting the prescaler).
-///
-/// Example usage (works without anything connected):
-///
-///     from pyb import CAN
-///     can = pyb.CAN(1, pyb.CAN.LOOPBACK)
-///     can.send('message!', 123)   # send message with id 123
-///     can.recv(0)                 # receive message on FIFO 0
-
-typedef enum _rx_state_t {
-    RX_STATE_FIFO_EMPTY = 0,
-    RX_STATE_MESSAGE_PENDING,
-    RX_STATE_FIFO_FULL,
-    RX_STATE_FIFO_OVERFLOW,
-} rx_state_t;
-
-typedef struct _pyb_can_obj_t {
-    mp_obj_base_t base;
-    mp_obj_t rxcallback0;
-    mp_obj_t rxcallback1;
-    mp_uint_t can_id : 8;
-    bool is_enabled : 1;
-    bool extframe : 1;
-    byte rx_state0;
-    byte rx_state1;
-    CAN_HandleTypeDef can;
-} pyb_can_obj_t;
-
-STATIC mp_obj_t pyb_can_deinit(mp_obj_t self_in);
-
-STATIC uint8_t can2_start_bank = 14;
-
-// assumes Init parameters have been set up correctly
-STATIC bool can_init(pyb_can_obj_t *can_obj) {
-    CAN_TypeDef *CANx = NULL;
-
-    uint32_t GPIO_Pin = 0;
-    uint8_t  GPIO_AF_CANx = 0;
-    GPIO_TypeDef* GPIO_Port = NULL;
-
-    switch (can_obj->can_id) {
-        // CAN1 is on RX,TX = Y3,Y4 = PB9,PB9
-        case PYB_CAN_1:
-            CANx = CAN1;
-            GPIO_AF_CANx = GPIO_AF9_CAN1;
-            GPIO_Port = GPIOB;
-            GPIO_Pin = GPIO_PIN_8 | GPIO_PIN_9;
-            __CAN1_CLK_ENABLE();
-            break;
-
-        // CAN2 is on RX,TX = Y5,Y6 = PB12,PB13
-        case PYB_CAN_2:
-            CANx = CAN2;
-            GPIO_AF_CANx = GPIO_AF9_CAN2;
-            GPIO_Port = GPIOB;
-            GPIO_Pin = GPIO_PIN_12 | GPIO_PIN_13;
-            __CAN1_CLK_ENABLE(); // CAN2 is a "slave" and needs CAN1 enabled as well
-            __CAN2_CLK_ENABLE();
-            break;
-
-        default:
-            return false;
-    }
-
-    // init GPIO
-    GPIO_InitTypeDef GPIO_InitStructure;
-    GPIO_InitStructure.Pin = GPIO_Pin;
-    GPIO_InitStructure.Speed = GPIO_SPEED_HIGH;
-    GPIO_InitStructure.Mode = GPIO_MODE_AF_PP;
-    GPIO_InitStructure.Pull = GPIO_PULLUP;
-    GPIO_InitStructure.Alternate = GPIO_AF_CANx;
-    HAL_GPIO_Init(GPIO_Port, &GPIO_InitStructure);
-
-    // init CANx
-    can_obj->can.Instance = CANx;
-    HAL_CAN_Init(&can_obj->can);
-
-    can_obj->is_enabled = true;
-
-    return true;
-}
-
-void can_init0(void) {
-    for (uint i = 0; i < MP_ARRAY_SIZE(MP_STATE_PORT(pyb_can_obj_all)); i++) {
-        MP_STATE_PORT(pyb_can_obj_all)[i] = NULL;
-    }
-}
-
-void can_deinit(void) {
-    for (int i = 0; i < MP_ARRAY_SIZE(MP_STATE_PORT(pyb_can_obj_all)); i++) {
-        pyb_can_obj_t *can_obj = MP_STATE_PORT(pyb_can_obj_all)[i];
-        if (can_obj != NULL) {
-            pyb_can_deinit(can_obj);
-        }
-    }
-}
-
-STATIC void can_clearfilter(uint32_t f) {
-    CAN_FilterConfTypeDef filter;
-
-    filter.FilterIdHigh         = 0;
-    filter.FilterIdLow          = 0;
-    filter.FilterMaskIdHigh     = 0;
-    filter.FilterMaskIdLow      = 0;
-    filter.FilterFIFOAssignment = CAN_FILTER_FIFO0;
-    filter.FilterNumber         = f;
-    filter.FilterMode           = CAN_FILTERMODE_IDMASK;
-    filter.FilterScale          = CAN_FILTERSCALE_16BIT;
-    filter.FilterActivation     = DISABLE;
-    filter.BankNumber           = can2_start_bank;
-
-    HAL_CAN_ConfigFilter(NULL, &filter);
-}
-
-// We have our own version of CAN transmit so we can handle Timeout=0 correctly.
-STATIC HAL_StatusTypeDef CAN_Transmit(CAN_HandleTypeDef *hcan, uint32_t Timeout) {
-    uint32_t transmitmailbox;
-    uint32_t tickstart;
-    uint32_t rqcpflag;
-    uint32_t txokflag;
-
-    // Check the parameters
-    assert_param(IS_CAN_IDTYPE(hcan->pTxMsg->IDE));
-    assert_param(IS_CAN_RTR(hcan->pTxMsg->RTR));
-    assert_param(IS_CAN_DLC(hcan->pTxMsg->DLC));
-
-    // Select one empty transmit mailbox
-    if ((hcan->Instance->TSR&CAN_TSR_TME0) == CAN_TSR_TME0) {
-        transmitmailbox = CAN_TXMAILBOX_0;
-        rqcpflag = CAN_FLAG_RQCP0;
-        txokflag = CAN_FLAG_TXOK0;
-    } else if ((hcan->Instance->TSR&CAN_TSR_TME1) == CAN_TSR_TME1) {
-        transmitmailbox = CAN_TXMAILBOX_1;
-        rqcpflag = CAN_FLAG_RQCP1;
-        txokflag = CAN_FLAG_TXOK1;
-    } else if ((hcan->Instance->TSR&CAN_TSR_TME2) == CAN_TSR_TME2) {
-        transmitmailbox = CAN_TXMAILBOX_2;
-        rqcpflag = CAN_FLAG_RQCP2;
-        txokflag = CAN_FLAG_TXOK2;
-    } else {
-        transmitmailbox = CAN_TXSTATUS_NOMAILBOX;
-    }
-
-    if (transmitmailbox != CAN_TXSTATUS_NOMAILBOX) {
-        // Set up the Id
-        hcan->Instance->sTxMailBox[transmitmailbox].TIR &= CAN_TI0R_TXRQ;
-        if (hcan->pTxMsg->IDE == CAN_ID_STD) {
-            assert_param(IS_CAN_STDID(hcan->pTxMsg->StdId));
-            hcan->Instance->sTxMailBox[transmitmailbox].TIR |= ((hcan->pTxMsg->StdId << 21) | \
-                                                        hcan->pTxMsg->RTR);
-        } else {
-            assert_param(IS_CAN_EXTID(hcan->pTxMsg->ExtId));
-            hcan->Instance->sTxMailBox[transmitmailbox].TIR |= ((hcan->pTxMsg->ExtId << 3) | \
-                                                        hcan->pTxMsg->IDE | \
-                                                        hcan->pTxMsg->RTR);
-        }
-
-        // Set up the DLC
-        hcan->pTxMsg->DLC &= (uint8_t)0x0000000F;
-        hcan->Instance->sTxMailBox[transmitmailbox].TDTR &= (uint32_t)0xFFFFFFF0;
-        hcan->Instance->sTxMailBox[transmitmailbox].TDTR |= hcan->pTxMsg->DLC;
-
-        // Set up the data field
-        hcan->Instance->sTxMailBox[transmitmailbox].TDLR = (((uint32_t)hcan->pTxMsg->Data[3] << 24) |
-                                                ((uint32_t)hcan->pTxMsg->Data[2] << 16) |
-                                                ((uint32_t)hcan->pTxMsg->Data[1] << 8) |
-                                                ((uint32_t)hcan->pTxMsg->Data[0]));
-        hcan->Instance->sTxMailBox[transmitmailbox].TDHR = (((uint32_t)hcan->pTxMsg->Data[7] << 24) |
-                                                ((uint32_t)hcan->pTxMsg->Data[6] << 16) |
-                                                ((uint32_t)hcan->pTxMsg->Data[5] << 8) |
-                                                ((uint32_t)hcan->pTxMsg->Data[4]));
-        // Request transmission
-        hcan->Instance->sTxMailBox[transmitmailbox].TIR |= CAN_TI0R_TXRQ;
-
-        if (Timeout == 0) {
-            return HAL_OK;
-        }
-
-        // Get tick
-        tickstart = HAL_GetTick();
-        // Check End of transmission flag
-        while (!(__HAL_CAN_TRANSMIT_STATUS(hcan, transmitmailbox))) {
-            // Check for the Timeout
-            if (Timeout != HAL_MAX_DELAY) {
-                if ((HAL_GetTick() - tickstart) > Timeout) {
-                    // When the timeout expires, we try to abort the transmission of the packet
-                    __HAL_CAN_CANCEL_TRANSMIT(hcan, transmitmailbox);
-                    while (!__HAL_CAN_GET_FLAG(hcan, rqcpflag)) {
-                    }
-                    if (__HAL_CAN_GET_FLAG(hcan, txokflag)) {
-                        // The abort attempt failed and the message was sent properly
-                        return HAL_OK;
-                    } else {
-                        return HAL_TIMEOUT;
-                    }
-                }
-            }
-        }
-        return HAL_OK;
-    } else {
-        return HAL_BUSY;
-    }
-}
-
-/******************************************************************************/
-// MicroPython bindings
-
-STATIC void pyb_can_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t kind) {
-    pyb_can_obj_t *self = self_in;
-    if (!self->is_enabled) {
-        mp_printf(print, "CAN(%u)", self->can_id);
-    } else {
-        mp_printf(print, "CAN(%u, CAN.", self->can_id);
-        qstr mode;
-        switch (self->can.Init.Mode) {
-            case CAN_MODE_NORMAL: mode = MP_QSTR_NORMAL; break;
-            case CAN_MODE_LOOPBACK: mode = MP_QSTR_LOOPBACK; break;
-            case CAN_MODE_SILENT: mode = MP_QSTR_SILENT; break;
-            case CAN_MODE_SILENT_LOOPBACK: default: mode = MP_QSTR_SILENT_LOOPBACK; break;
-        }
-        mp_printf(print, "%q, extframe=", mode);
-        if (self->extframe) {
-            mode = MP_QSTR_True;
-        } else {
-            mode = MP_QSTR_False;
-        }
-        mp_printf(print, "%q)", mode);
-    }
-}
-
-// init(mode, extframe=False, prescaler=100, *, sjw=1, bs1=6, bs2=8)
-STATIC mp_obj_t pyb_can_init_helper(pyb_can_obj_t *self, size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
-    static const mp_arg_t allowed_args[] = {
-        { MP_QSTR_mode,         MP_ARG_REQUIRED | MP_ARG_INT,   {.u_int  = CAN_MODE_NORMAL} },
-        { MP_QSTR_extframe,     MP_ARG_BOOL,                    {.u_bool = false} },
-        { MP_QSTR_prescaler,    MP_ARG_INT,                     {.u_int  = 100} },
-        { MP_QSTR_sjw,          MP_ARG_KW_ONLY | MP_ARG_INT,    {.u_int = 1} },
-        { MP_QSTR_bs1,          MP_ARG_KW_ONLY | MP_ARG_INT,    {.u_int = 6} },
-        { MP_QSTR_bs2,          MP_ARG_KW_ONLY | MP_ARG_INT,    {.u_int = 8} },
-    };
-
-    // parse args
-    mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
-    mp_arg_parse_all(n_args, pos_args, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
-
-    self->extframe = args[1].u_bool;
-
-    // set the CAN configuration values
-    memset(&self->can, 0, sizeof(self->can));
-    CAN_InitTypeDef *init = &self->can.Init;
-    init->Mode = args[0].u_int << 4; // shift-left so modes fit in a small-int
-    init->Prescaler = args[2].u_int;
-    init->SJW = ((args[3].u_int - 1) & 3) << 24;
-    init->BS1 = ((args[4].u_int - 1) & 0xf) << 16;
-    init->BS2 = ((args[5].u_int - 1) & 7) << 20;
-    init->TTCM = DISABLE;
-    init->ABOM = DISABLE;
-    init->AWUM = DISABLE;
-    init->NART = DISABLE;
-    init->RFLM = DISABLE;
-    init->TXFP = DISABLE;
-
-    // init CAN (if it fails, it's because the port doesn't exist)
-    if (!can_init(self)) {
-        nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "CAN(%d) doesn't exist", self->can_id));
-    }
-
-    return mp_const_none;
-}
-
-/// \classmethod \constructor(bus, ...)
-///
-/// Construct a CAN object on the given bus.  `bus` can be 1-2, or 'YA' or 'YB'.
-/// With no additional parameters, the CAN object is created but not
-/// initialised (it has the settings from the last initialisation of
-/// the bus, if any).  If extra arguments are given, the bus is initialised.
-/// See `init` for parameters of initialisation.
-///
-/// The physical pins of the CAN busses are:
-///
-///   - `CAN(1)` is on `YA`: `(RX, TX) = (Y3, Y4) = (PB8, PB9)`
-///   - `CAN(2)` is on `YB`: `(RX, TX) = (Y5, Y6) = (PB12, PB13)`
-STATIC mp_obj_t pyb_can_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *args) {
-    // check arguments
-    mp_arg_check_num(n_args, n_kw, 1, MP_OBJ_FUN_ARGS_MAX, true);
-
-    // work out port
-    mp_uint_t can_idx;
-    if (MP_OBJ_IS_STR(args[0])) {
-        const char *port = mp_obj_str_get_str(args[0]);
-        if (0) {
-        #ifdef MICROPY_HW_CAN1_NAME
-        } else if (strcmp(port, MICROPY_HW_CAN1_NAME) == 0) {
-            can_idx = PYB_CAN_1;
-        #endif
-        #ifdef MICROPY_HW_CAN2_NAME
-        } else if (strcmp(port, MICROPY_HW_CAN2_NAME) == 0) {
-            can_idx = PYB_CAN_2;
-        #endif
-        } else {
-            nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "CAN(%s) doesn't exist", port));
-        }
-    } else {
-        can_idx = mp_obj_get_int(args[0]);
-    }
-    if (can_idx < 1 || can_idx > MP_ARRAY_SIZE(MP_STATE_PORT(pyb_can_obj_all))) {
-        nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "CAN(%d) doesn't exist", can_idx));
-    }
-
-    pyb_can_obj_t *self;
-    if (MP_STATE_PORT(pyb_can_obj_all)[can_idx - 1] == NULL) {
-        self = m_new_obj(pyb_can_obj_t);
-        self->base.type = &pyb_can_type;
-        self->can_id = can_idx;
-        self->is_enabled = false;
-        MP_STATE_PORT(pyb_can_obj_all)[can_idx - 1] = self;
-    } else {
-        self = MP_STATE_PORT(pyb_can_obj_all)[can_idx - 1];
-    }
-
-    if (!self->is_enabled || n_args > 1) {
-        if (self->is_enabled) {
-            // The caller is requesting a reconfiguration of the hardware
-            // this can only be done if the hardware is in init mode
-            pyb_can_deinit(self);
-        }
-
-        self->rxcallback0 = mp_const_none;
-        self->rxcallback1 = mp_const_none;
-        self->rx_state0 = RX_STATE_FIFO_EMPTY;
-        self->rx_state1 = RX_STATE_FIFO_EMPTY;
-
-        if (n_args > 1 || n_kw > 0) {
-            // start the peripheral
-            mp_map_t kw_args;
-            mp_map_init_fixed_table(&kw_args, n_kw, args + n_args);
-            pyb_can_init_helper(self, n_args - 1, args + 1, &kw_args);
-        }
-    }
-
-    return self;
-}
-
-STATIC mp_obj_t pyb_can_init(size_t n_args, const mp_obj_t *args, mp_map_t *kw_args) {
-    return pyb_can_init_helper(args[0], n_args - 1, args + 1, kw_args);
-}
-STATIC MP_DEFINE_CONST_FUN_OBJ_KW(pyb_can_init_obj, 1, pyb_can_init);
-
-/// \method deinit()
-/// Turn off the CAN bus.
-STATIC mp_obj_t pyb_can_deinit(mp_obj_t self_in) {
-    pyb_can_obj_t *self = self_in;
-    self->is_enabled = false;
-    HAL_CAN_DeInit(&self->can);
-    if (self->can.Instance == CAN1) {
-        HAL_NVIC_DisableIRQ(CAN1_RX0_IRQn);
-        HAL_NVIC_DisableIRQ(CAN1_RX1_IRQn);
-        __CAN1_FORCE_RESET();
-        __CAN1_RELEASE_RESET();
-        __CAN1_CLK_DISABLE();
-    } else if (self->can.Instance == CAN2) {
-        HAL_NVIC_DisableIRQ(CAN2_RX0_IRQn);
-        HAL_NVIC_DisableIRQ(CAN2_RX1_IRQn);
-        __CAN2_FORCE_RESET();
-        __CAN2_RELEASE_RESET();
-        __CAN2_CLK_DISABLE();
-    }
-    return mp_const_none;
-}
-STATIC MP_DEFINE_CONST_FUN_OBJ_1(pyb_can_deinit_obj, pyb_can_deinit);
-
-/// \method any(fifo)
-/// Return `True` if any message waiting on the FIFO, else `False`.
-STATIC mp_obj_t pyb_can_any(mp_obj_t self_in, mp_obj_t fifo_in) {
-    pyb_can_obj_t *self = self_in;
-    mp_int_t fifo = mp_obj_get_int(fifo_in);
-    if (fifo == 0) {
-        if (__HAL_CAN_MSG_PENDING(&self->can, CAN_FIFO0) != 0) {
-            return mp_const_true;
-        }
-    } else {
-        if (__HAL_CAN_MSG_PENDING(&self->can, CAN_FIFO1) != 0) {
-            return mp_const_true;
-        }
-    }
-    return mp_const_false;
-}
-STATIC MP_DEFINE_CONST_FUN_OBJ_2(pyb_can_any_obj, pyb_can_any);
-
-/// \method send(send, addr, *, timeout=5000)
-/// Send a message on the bus:
-///
-///   - `send` is the data to send (an integer to send, or a buffer object).
-///   - `addr` is the address to send to
-///   - `timeout` is the timeout in milliseconds to wait for the send.
-///
-/// Return value: `None`.
-STATIC mp_obj_t pyb_can_send(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
-    static const mp_arg_t allowed_args[] = {
-        { MP_QSTR_data,    MP_ARG_REQUIRED | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
-        { MP_QSTR_id,      MP_ARG_REQUIRED | MP_ARG_INT, {.u_int = 0} },
-        { MP_QSTR_timeout, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0} },
-        { MP_QSTR_rtr,     MP_ARG_KW_ONLY | MP_ARG_BOOL, {.u_bool = false} },
-    };
-
-    // parse args
-    pyb_can_obj_t *self = pos_args[0];
-    mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
-    mp_arg_parse_all(n_args - 1, pos_args + 1, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
-
-    // get the buffer to send from
-    mp_buffer_info_t bufinfo;
-    uint8_t data[1];
-    pyb_buf_get_for_send(args[0].u_obj, &bufinfo, data);
-
-    if (bufinfo.len > 8) {
-        mp_raise_ValueError("CAN data field too long");
-    }
-
-    // send the data
-    CanTxMsgTypeDef tx_msg;
-    if (self->extframe) {
-        tx_msg.ExtId = args[1].u_int & 0x1FFFFFFF;
-        tx_msg.IDE = CAN_ID_EXT;
-    } else {
-        tx_msg.StdId = args[1].u_int & 0x7FF;
-        tx_msg.IDE = CAN_ID_STD;
-    }
-    if (args[3].u_bool == false) {
-        tx_msg.RTR = CAN_RTR_DATA;
-    } else  {
-        tx_msg.RTR = CAN_RTR_REMOTE;
-    }
-    tx_msg.DLC = bufinfo.len;
-    for (mp_uint_t i = 0; i < bufinfo.len; i++) {
-        tx_msg.Data[i] = ((byte*)bufinfo.buf)[i]; // Data is uint32_t but holds only 1 byte
-    }
-
-    self->can.pTxMsg = &tx_msg;
-    HAL_StatusTypeDef status = CAN_Transmit(&self->can, args[2].u_int);
-
-    if (status != HAL_OK) {
-        mp_hal_raise(status);
-    }
-
-    return mp_const_none;
-}
-STATIC MP_DEFINE_CONST_FUN_OBJ_KW(pyb_can_send_obj, 1, pyb_can_send);
-
-/// \method recv(fifo, *, timeout=5000)
-///
-/// Receive data on the bus:
-///
-///   - `fifo` is an integer, which is the FIFO to receive on
-///   - `timeout` is the timeout in milliseconds to wait for the receive.
-///
-/// Return value: buffer of data bytes.
-STATIC mp_obj_t pyb_can_recv(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
-    static const mp_arg_t allowed_args[] = {
-        { MP_QSTR_fifo,    MP_ARG_REQUIRED | MP_ARG_INT, {.u_int = 0} },
-        { MP_QSTR_timeout, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 5000} },
-    };
-
-    // parse args
-    pyb_can_obj_t *self = pos_args[0];
-    mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
-    mp_arg_parse_all(n_args - 1, pos_args + 1, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
-
-    // receive the data
-    CanRxMsgTypeDef rx_msg;
-    self->can.pRxMsg = self->can.pRx1Msg = &rx_msg;
-    HAL_StatusTypeDef status = HAL_CAN_Receive(&self->can, args[0].u_int, args[1].u_int);
-
-    if (status != HAL_OK) {
-        mp_hal_raise(status);
-    }
-
-    // Manage the rx state machine
-    if ((args[0].u_int == CAN_FIFO0 && self->rxcallback0 != mp_const_none) ||
-        (args[0].u_int == CAN_FIFO1 && self->rxcallback1 != mp_const_none)) {
-        byte *state = (args[0].u_int == CAN_FIFO0) ? &self->rx_state0 : &self->rx_state1;
-
-        switch (*state) {
-        case RX_STATE_FIFO_EMPTY:
-            break;
-        case RX_STATE_MESSAGE_PENDING:
-            if (__HAL_CAN_MSG_PENDING(&self->can, args[0].u_int) == 0) {
-                // Fifo is empty
-                __HAL_CAN_ENABLE_IT(&self->can, (args[0].u_int == CAN_FIFO0) ? CAN_IT_FMP0 : CAN_IT_FMP1);
-                *state = RX_STATE_FIFO_EMPTY;
-            }
-            break;
-        case RX_STATE_FIFO_FULL:
-            __HAL_CAN_ENABLE_IT(&self->can, (args[0].u_int == CAN_FIFO0) ? CAN_IT_FF0 : CAN_IT_FF1);
-            *state = RX_STATE_MESSAGE_PENDING;
-            break;
-        case RX_STATE_FIFO_OVERFLOW:
-            __HAL_CAN_ENABLE_IT(&self->can, (args[0].u_int == CAN_FIFO0) ? CAN_IT_FOV0 : CAN_IT_FOV1);
-            __HAL_CAN_ENABLE_IT(&self->can, (args[0].u_int == CAN_FIFO0) ? CAN_IT_FF0  : CAN_IT_FF1);
-            *state = RX_STATE_MESSAGE_PENDING;
-            break;
-        }
-    }
-
-    // return the received data
-    // TODO use a namedtuple (when namedtuple types can be stored in ROM)
-    mp_obj_tuple_t *tuple = mp_obj_new_tuple(4, NULL);
-    if (rx_msg.IDE == CAN_ID_STD) {
-        tuple->items[0] = MP_OBJ_NEW_SMALL_INT(rx_msg.StdId);
-    } else {
-        tuple->items[0] = MP_OBJ_NEW_SMALL_INT(rx_msg.ExtId);
-    }
-    tuple->items[1] = rx_msg.RTR == CAN_RTR_REMOTE ? mp_const_true : mp_const_false;
-    tuple->items[2] = MP_OBJ_NEW_SMALL_INT(rx_msg.FMI);
-    vstr_t vstr;
-    vstr_init_len(&vstr, rx_msg.DLC);
-    for (mp_uint_t i = 0; i < rx_msg.DLC; i++) {
-        vstr.buf[i] = rx_msg.Data[i]; // Data is uint32_t but holds only 1 byte
-    }
-    tuple->items[3] = mp_obj_new_str_from_vstr(&mp_type_bytes, &vstr);
-    return tuple;
-}
-STATIC MP_DEFINE_CONST_FUN_OBJ_KW(pyb_can_recv_obj, 1, pyb_can_recv);
-
-/// \class method initfilterbanks
-///
-/// Set up the filterbanks. All filter will be disabled and set to their reset states.
-///
-///   - `banks` is an integer that sets how many filter banks that are reserved for CAN1.
-///     0  -> no filters assigned for CAN1
-///     28 -> all filters are assigned to CAN1
-///     CAN2 will get the rest of the 28 available.
-///
-/// Return value: none.
-STATIC mp_obj_t pyb_can_initfilterbanks(mp_obj_t self, mp_obj_t bank_in) {
-    can2_start_bank = mp_obj_get_int(bank_in);
-
-    for (int f = 0; f < 28; f++) {
-        can_clearfilter(f);
-    }
-
-    return mp_const_none;
-}
-STATIC MP_DEFINE_CONST_FUN_OBJ_2(pyb_can_initfilterbanks_fun_obj, pyb_can_initfilterbanks);
-STATIC MP_DEFINE_CONST_CLASSMETHOD_OBJ(pyb_can_initfilterbanks_obj, (const mp_obj_t)&pyb_can_initfilterbanks_fun_obj);
-
-STATIC mp_obj_t pyb_can_clearfilter(mp_obj_t self_in, mp_obj_t bank_in) {
-    pyb_can_obj_t *self = self_in;
-    mp_int_t f = mp_obj_get_int(bank_in);
-    if (self->can_id == 2) {
-        f += can2_start_bank;
-    }
-    can_clearfilter(f);
-    return mp_const_none;
-}
-STATIC MP_DEFINE_CONST_FUN_OBJ_2(pyb_can_clearfilter_obj, pyb_can_clearfilter);
-
-/// Configures a filterbank
-/// Return value: `None`.
-#define EXTENDED_ID_TO_16BIT_FILTER(id) (((id & 0xC00000) >> 13) | ((id & 0x38000) >> 15)) | 8
-STATIC mp_obj_t pyb_can_setfilter(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
-    static const mp_arg_t allowed_args[] = {
-        { MP_QSTR_bank,     MP_ARG_REQUIRED | MP_ARG_INT, {.u_int = 0} },
-        { MP_QSTR_mode,     MP_ARG_REQUIRED | MP_ARG_INT, {.u_int = 0} },
-        { MP_QSTR_fifo,     MP_ARG_REQUIRED | MP_ARG_INT, {.u_int = CAN_FILTER_FIFO0} },
-        { MP_QSTR_params,   MP_ARG_REQUIRED | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
-        { MP_QSTR_rtr,      MP_ARG_KW_ONLY  | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
-    };
-
-    // parse args
-    pyb_can_obj_t *self = pos_args[0];
-    mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
-    mp_arg_parse_all(n_args - 1, pos_args + 1, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
-
-    size_t len;
-    size_t rtr_len;
-    mp_uint_t rtr_masks[4] = {0, 0, 0, 0};
-    mp_obj_t *rtr_flags;
-    mp_obj_t *params;
-    mp_obj_get_array(args[3].u_obj, &len, &params);
-    if (args[4].u_obj != MP_OBJ_NULL){
-        mp_obj_get_array(args[4].u_obj, &rtr_len, &rtr_flags);
-    }
-
-    CAN_FilterConfTypeDef filter;
-    if (args[1].u_int == MASK16 || args[1].u_int == LIST16) {
-        if (len != 4) {
-            goto error;
-        }
-        filter.FilterScale = CAN_FILTERSCALE_16BIT;
-        if (self->extframe) {
-            if (args[4].u_obj != MP_OBJ_NULL) {
-                if (args[1].u_int == MASK16) {
-                    rtr_masks[0] = mp_obj_get_int(rtr_flags[0]) ? 0x02 : 0;
-                    rtr_masks[1] = 0x02;
-                    rtr_masks[2] = mp_obj_get_int(rtr_flags[1]) ? 0x02 : 0;
-                    rtr_masks[3] = 0x02;
-                } else {  // LIST16
-                    rtr_masks[0] = mp_obj_get_int(rtr_flags[0]) ? 0x02 : 0;
-                    rtr_masks[1] = mp_obj_get_int(rtr_flags[1]) ? 0x02 : 0;
-                    rtr_masks[2] = mp_obj_get_int(rtr_flags[2]) ? 0x02 : 0;
-                    rtr_masks[3] = mp_obj_get_int(rtr_flags[3]) ? 0x02 : 0;
-                }
-            }
-            filter.FilterIdLow      = EXTENDED_ID_TO_16BIT_FILTER(mp_obj_get_int(params[0])) | rtr_masks[0]; // id1
-            filter.FilterMaskIdLow  = EXTENDED_ID_TO_16BIT_FILTER(mp_obj_get_int(params[1])) | rtr_masks[1]; // mask1
-            filter.FilterIdHigh     = EXTENDED_ID_TO_16BIT_FILTER(mp_obj_get_int(params[2])) | rtr_masks[2]; // id2
-            filter.FilterMaskIdHigh = EXTENDED_ID_TO_16BIT_FILTER(mp_obj_get_int(params[3])) | rtr_masks[3]; // mask2
-        } else { // Basic frames
-            if (args[4].u_obj != MP_OBJ_NULL) {
-                if (args[1].u_int == MASK16) {
-                    rtr_masks[0] = mp_obj_get_int(rtr_flags[0]) ? 0x10 : 0;
-                    rtr_masks[1] = 0x10;
-                    rtr_masks[2] = mp_obj_get_int(rtr_flags[1]) ? 0x10 : 0;
-                    rtr_masks[3] = 0x10;
-                } else {  // LIST16
-                    rtr_masks[0] = mp_obj_get_int(rtr_flags[0]) ? 0x10 : 0;
-                    rtr_masks[1] = mp_obj_get_int(rtr_flags[1]) ? 0x10 : 0;
-                    rtr_masks[2] = mp_obj_get_int(rtr_flags[2]) ? 0x10 : 0;
-                    rtr_masks[3] = mp_obj_get_int(rtr_flags[3]) ? 0x10 : 0;
-                }
-            }
-            filter.FilterIdLow      = (mp_obj_get_int(params[0]) << 5) | rtr_masks[0]; // id1
-            filter.FilterMaskIdLow  = (mp_obj_get_int(params[1]) << 5) | rtr_masks[1]; // mask1
-            filter.FilterIdHigh     = (mp_obj_get_int(params[2]) << 5) | rtr_masks[2]; // id2
-            filter.FilterMaskIdHigh = (mp_obj_get_int(params[3]) << 5) | rtr_masks[3]; // mask2
-        }
-        if (args[1].u_int == MASK16) {
-            filter.FilterMode  = CAN_FILTERMODE_IDMASK;
-        }
-        if (args[1].u_int == LIST16) {
-            filter.FilterMode  = CAN_FILTERMODE_IDLIST;
-        }
-    }
-    else if (args[1].u_int == MASK32 || args[1].u_int == LIST32) {
-        if (len != 2) {
-            goto error;
-        }
-        filter.FilterScale = CAN_FILTERSCALE_32BIT;
-        if (args[4].u_obj != MP_OBJ_NULL) {
-            if (args[1].u_int == MASK32) {
-                rtr_masks[0] = mp_obj_get_int(rtr_flags[0]) ? 0x02 : 0;
-                rtr_masks[1] = 0x02;
-            } else {  // LIST32
-                rtr_masks[0] = mp_obj_get_int(rtr_flags[0]) ? 0x02 : 0;
-                rtr_masks[1] = mp_obj_get_int(rtr_flags[1]) ? 0x02 : 0;
-            }
-        }
-        filter.FilterIdHigh     = (mp_obj_get_int(params[0]) & 0x1FFFE000)  >> 13;
-        filter.FilterIdLow      = (((mp_obj_get_int(params[0]) & 0x00001FFF) << 3) | 4) | rtr_masks[0];
-        filter.FilterMaskIdHigh = (mp_obj_get_int(params[1]) & 0x1FFFE000 ) >> 13;
-        filter.FilterMaskIdLow  = (((mp_obj_get_int(params[1]) & 0x00001FFF) << 3) | 4) | rtr_masks[1];
-        if (args[1].u_int == MASK32) {
-            filter.FilterMode  = CAN_FILTERMODE_IDMASK;
-        }
-        if (args[1].u_int == LIST32) {
-            filter.FilterMode  = CAN_FILTERMODE_IDLIST;
-        }
-    } else {
-        goto error;
-    }
-
-    filter.FilterFIFOAssignment = args[2].u_int; // fifo
-    filter.FilterNumber = args[0].u_int; // bank
-    if (self->can_id == 1) {
-        if (filter.FilterNumber >= can2_start_bank) {
-            goto error;
-        }
-    } else {
-        filter.FilterNumber = filter.FilterNumber + can2_start_bank;
-        if (filter.FilterNumber > 27) {
-            goto error;
-        }
-    }
-    filter.FilterActivation = ENABLE;
-    filter.BankNumber = can2_start_bank;
-    HAL_CAN_ConfigFilter(&self->can, &filter);
-
-    return mp_const_none;
-
-error:
-    mp_raise_ValueError("CAN filter parameter error");
-}
-STATIC MP_DEFINE_CONST_FUN_OBJ_KW(pyb_can_setfilter_obj, 1, pyb_can_setfilter);
-
-STATIC mp_obj_t pyb_can_rxcallback(mp_obj_t self_in, mp_obj_t fifo_in, mp_obj_t callback_in) {
-    pyb_can_obj_t *self = self_in;
-    mp_int_t fifo = mp_obj_get_int(fifo_in);
-    mp_obj_t *callback;
-
-    callback = (fifo == 0) ? &self->rxcallback0 : &self->rxcallback1;
-    if (callback_in == mp_const_none) {
-        __HAL_CAN_DISABLE_IT(&self->can, (fifo == 0) ? CAN_IT_FMP0 : CAN_IT_FMP1);
-        __HAL_CAN_DISABLE_IT(&self->can, (fifo == 0) ? CAN_IT_FF0 : CAN_IT_FF1);
-        __HAL_CAN_DISABLE_IT(&self->can, (fifo == 0) ? CAN_IT_FOV0 : CAN_IT_FOV1);
-        __HAL_CAN_CLEAR_FLAG(&self->can, (fifo == CAN_FIFO0) ? CAN_FLAG_FF0 : CAN_FLAG_FF1);
-        __HAL_CAN_CLEAR_FLAG(&self->can, (fifo == CAN_FIFO0) ? CAN_FLAG_FOV0 : CAN_FLAG_FOV1);
-        *callback = mp_const_none;
-    } else if (*callback != mp_const_none) {
-        // Rx call backs has already been initialized
-        // only the callback function should be changed
-        *callback = callback_in;
-    } else if (mp_obj_is_callable(callback_in)) {
-        *callback = callback_in;
-        uint32_t irq;
-        if (self->can_id == PYB_CAN_1) {
-            irq = (fifo == 0) ? CAN1_RX0_IRQn : CAN1_RX1_IRQn;
-        } else {
-            irq = (fifo == 0) ? CAN2_RX0_IRQn : CAN2_RX1_IRQn;
-        }
-        HAL_NVIC_SetPriority(irq, IRQ_PRI_CAN, IRQ_SUBPRI_CAN);
-        HAL_NVIC_EnableIRQ(irq);
-        __HAL_CAN_ENABLE_IT(&self->can, (fifo == 0) ? CAN_IT_FMP0 : CAN_IT_FMP1);
-        __HAL_CAN_ENABLE_IT(&self->can, (fifo == 0) ? CAN_IT_FF0  : CAN_IT_FF1);
-        __HAL_CAN_ENABLE_IT(&self->can, (fifo == 0) ? CAN_IT_FOV0 : CAN_IT_FOV1);
-    }
-    return mp_const_none;
-}
-STATIC MP_DEFINE_CONST_FUN_OBJ_3(pyb_can_rxcallback_obj, pyb_can_rxcallback);
-
-STATIC const mp_rom_map_elem_t pyb_can_locals_dict_table[] = {
-    // instance methods
-    { MP_ROM_QSTR(MP_QSTR_init), MP_ROM_PTR(&pyb_can_init_obj) },
-    { MP_ROM_QSTR(MP_QSTR_deinit), MP_ROM_PTR(&pyb_can_deinit_obj) },
-    { MP_ROM_QSTR(MP_QSTR_any), MP_ROM_PTR(&pyb_can_any_obj) },
-    { MP_ROM_QSTR(MP_QSTR_send), MP_ROM_PTR(&pyb_can_send_obj) },
-    { MP_ROM_QSTR(MP_QSTR_recv), MP_ROM_PTR(&pyb_can_recv_obj) },
-    { MP_ROM_QSTR(MP_QSTR_initfilterbanks), MP_ROM_PTR(&pyb_can_initfilterbanks_obj) },
-    { MP_ROM_QSTR(MP_QSTR_setfilter), MP_ROM_PTR(&pyb_can_setfilter_obj) },
-    { MP_ROM_QSTR(MP_QSTR_clearfilter), MP_ROM_PTR(&pyb_can_clearfilter_obj) },
-    { MP_ROM_QSTR(MP_QSTR_rxcallback), MP_ROM_PTR(&pyb_can_rxcallback_obj) },
-
-    // class constants
-    // Note: we use the ST constants >> 4 so they fit in a small-int.  The
-    // right-shift is undone when the constants are used in the init function.
-    { MP_ROM_QSTR(MP_QSTR_NORMAL), MP_ROM_INT(CAN_MODE_NORMAL >> 4) },
-    { MP_ROM_QSTR(MP_QSTR_LOOPBACK), MP_ROM_INT(CAN_MODE_LOOPBACK >> 4) },
-    { MP_ROM_QSTR(MP_QSTR_SILENT), MP_ROM_INT(CAN_MODE_SILENT >> 4) },
-    { MP_ROM_QSTR(MP_QSTR_SILENT_LOOPBACK), MP_ROM_INT(CAN_MODE_SILENT_LOOPBACK >> 4) },
-    { MP_ROM_QSTR(MP_QSTR_MASK16), MP_ROM_INT(MASK16) },
-    { MP_ROM_QSTR(MP_QSTR_LIST16), MP_ROM_INT(LIST16) },
-    { MP_ROM_QSTR(MP_QSTR_MASK32), MP_ROM_INT(MASK32) },
-    { MP_ROM_QSTR(MP_QSTR_LIST32), MP_ROM_INT(LIST32) },
-};
-
-STATIC MP_DEFINE_CONST_DICT(pyb_can_locals_dict, pyb_can_locals_dict_table);
-
-mp_uint_t can_ioctl(mp_obj_t self_in, mp_uint_t request, mp_uint_t arg, int *errcode) {
-    pyb_can_obj_t *self = self_in;
-    mp_uint_t ret;
-    if (request == MP_STREAM_POLL) {
-        mp_uint_t flags = arg;
-        ret = 0;
-        if ((flags & MP_STREAM_POLL_RD)
-            && ((__HAL_CAN_MSG_PENDING(&self->can, CAN_FIFO0) != 0)
-                || (__HAL_CAN_MSG_PENDING(&self->can, CAN_FIFO1) != 0))) {
-            ret |= MP_STREAM_POLL_RD;
-        }
-        if ((flags & MP_STREAM_POLL_WR) && (self->can.Instance->TSR & CAN_TSR_TME)) {
-            ret |= MP_STREAM_POLL_WR;
-        }
-    } else {
-        *errcode = MP_EINVAL;
-        ret = -1;
-    }
-    return ret;
-}
-
-void can_rx_irq_handler(uint can_id, uint fifo_id) {
-    mp_obj_t callback;
-    pyb_can_obj_t *self;
-    mp_obj_t irq_reason = MP_OBJ_NEW_SMALL_INT(0);
-    byte *state;
-
-    self = MP_STATE_PORT(pyb_can_obj_all)[can_id - 1];
-
-    if (fifo_id == CAN_FIFO0) {
-        callback = self->rxcallback0;
-        state = &self->rx_state0;
-    } else {
-        callback = self->rxcallback1;
-        state = &self->rx_state1;
-    }
-
-    switch (*state) {
-        case RX_STATE_FIFO_EMPTY:
-            __HAL_CAN_DISABLE_IT(&self->can,  (fifo_id == CAN_FIFO0) ? CAN_IT_FMP0 : CAN_IT_FMP1);
-            irq_reason = MP_OBJ_NEW_SMALL_INT(0);
-            *state = RX_STATE_MESSAGE_PENDING;
-            break;
-        case RX_STATE_MESSAGE_PENDING:
-            __HAL_CAN_DISABLE_IT(&self->can, (fifo_id == CAN_FIFO0) ? CAN_IT_FF0 : CAN_IT_FF1);
-            __HAL_CAN_CLEAR_FLAG(&self->can, (fifo_id == CAN_FIFO0) ? CAN_FLAG_FF0 : CAN_FLAG_FF1);
-            irq_reason = MP_OBJ_NEW_SMALL_INT(1);
-            *state = RX_STATE_FIFO_FULL;
-            break;
-        case RX_STATE_FIFO_FULL:
-            __HAL_CAN_DISABLE_IT(&self->can, (fifo_id == CAN_FIFO0) ? CAN_IT_FOV0 : CAN_IT_FOV1);
-            __HAL_CAN_CLEAR_FLAG(&self->can, (fifo_id == CAN_FIFO0) ? CAN_FLAG_FOV0 : CAN_FLAG_FOV1);
-            irq_reason = MP_OBJ_NEW_SMALL_INT(2);
-            *state = RX_STATE_FIFO_OVERFLOW;
-            break;
-        case RX_STATE_FIFO_OVERFLOW:
-            // This should never happen
-            break;
-    }
-
-    if (callback != mp_const_none) {
-        mp_sched_lock();
-        gc_lock();
-        nlr_buf_t nlr;
-        if (nlr_push(&nlr) == 0) {
-            mp_call_function_2(callback, self, irq_reason);
-            nlr_pop();
-        } else {
-            // Uncaught exception; disable the callback so it doesn't run again.
-            pyb_can_rxcallback(self, MP_OBJ_NEW_SMALL_INT(fifo_id), mp_const_none);
-            printf("uncaught exception in CAN(%u) rx interrupt handler\n", self->can_id);
-            mp_obj_print_exception(&mp_plat_print, (mp_obj_t)nlr.ret_val);
-        }
-        gc_unlock();
-        mp_sched_unlock();
-    }
-}
-
-STATIC const mp_stream_p_t can_stream_p = {
-    //.read = can_read, // is read sensible for CAN?
-    //.write = can_write, // is write sensible for CAN?
-    .ioctl = can_ioctl,
-    .is_text = false,
-};
-
-const mp_obj_type_t pyb_can_type = {
-    { &mp_type_type },
-    .name = MP_QSTR_CAN,
-    .print = pyb_can_print,
-    .make_new = pyb_can_make_new,
-    .protocol = &can_stream_p,
-    .locals_dict = (mp_obj_t)&pyb_can_locals_dict,
-};
-
-#endif // MICROPY_HW_ENABLE_CAN