i2c.c 20.9 KB
Newer Older
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
/*
 * This file is part of the Micro Python project, http://micropython.org/
 *
 * The MIT License (MIT)
 *
 * Copyright (c) 2013, 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.
 */

27
28
29
#include <stdio.h>
#include <string.h>

30
#include "stm32f4xx_hal.h"
31

32
#include "mpconfig.h"
33
34
35
36
37
#include "nlr.h"
#include "misc.h"
#include "qstr.h"
#include "obj.h"
#include "runtime.h"
38
39
#include "pin.h"
#include "genhdr/pins.h"
40
#include "bufhelper.h"
41
42
#include "i2c.h"

43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
/// \moduleref pyb
/// \class I2C - a two-wire serial protocol
///
/// I2C is a two-wire protocol for communicating between devices.  At the physical
/// level it consists of 2 wires: SCL and SDA, the clock and data lines respectively.
///
/// I2C objects are created attached to a specific bus.  They can be initialised
/// when created, or initialised later on:
///
///     from pyb import I2C
///
///     i2c = I2C(1)                         # create on bus 1
///     i2c = I2C(1, I2C.MASTER)             # create and init as a master
///     i2c.init(I2C.MASTER, baudrate=20000) # init as a master
///     i2c.init(I2C.SLAVE, addr=0x42)       # init as a slave with given address
///     i2c.deinit()                         # turn off the peripheral
///
/// Printing the i2c object gives you information about its configuration.
///
/// Basic methods for slave are send and recv:
///
///     i2c.send('abc')      # send 3 bytes
///     i2c.send(0x42)       # send a single byte, given by the number
///     data = i2c.recv(3)   # receive 3 bytes
///
/// To receive inplace, first create a bytearray:
///
///     data = bytearray(3)  # create a buffer
///     i2c.recv(data)       # receive 3 bytes, writing them into data
///
/// You can specify a timeout (in ms):
///
///     i2c.send(b'123', timeout=2000)   # timout after 2 seconds
///
/// A master must specify the recipient's address:
///
///     i2c.init(I2C.MASTER)
///     i2c.send('123', 0x42)        # send 3 bytes to slave with address 0x42
///     i2c.send(b'456', addr=0x42)  # keyword for address
///
/// Master also has other methods:
///
///     i2c.is_ready(0x42)           # check if slave 0x42 is ready
///     i2c.scan()                   # scan for slaves on the bus, returning
///                                  #   a list of valid addresses
///     i2c.mem_read(3, 0x42, 2)     # read 3 bytes from memory of slave 0x42,
///                                  #   starting at address 2 in the slave
///     i2c.mem_write('abc', 0x42, 2, timeout=1000)
91

92
93
94
#define PYB_I2C_MASTER (0)
#define PYB_I2C_SLAVE  (1)

95
#if MICROPY_HW_ENABLE_I2C1
96
I2C_HandleTypeDef I2CHandle1 = {.Instance = NULL};
97
#endif
98
I2C_HandleTypeDef I2CHandle2 = {.Instance = NULL};
99

100
101
void i2c_init0(void) {
    // reset the I2C1 handles
102
#if MICROPY_HW_ENABLE_I2C1
103
104
    memset(&I2CHandle1, 0, sizeof(I2C_HandleTypeDef));
    I2CHandle1.Instance = I2C1;
105
#endif
106
107
    memset(&I2CHandle2, 0, sizeof(I2C_HandleTypeDef));
    I2CHandle2.Instance = I2C2;
108
109
}

110
void i2c_init(I2C_HandleTypeDef *i2c) {
111
    // init the GPIO lines
112
    GPIO_InitTypeDef GPIO_InitStructure;
113
114
115
116
    GPIO_InitStructure.Mode = GPIO_MODE_AF_OD;
    GPIO_InitStructure.Speed = GPIO_SPEED_FAST;
    GPIO_InitStructure.Pull = GPIO_NOPULL; // have external pull-up resistors on both lines

117
    const pin_obj_t *pins[2];
118
    if (0) {
119
#if MICROPY_HW_ENABLE_I2C1
120
    } else if (i2c == &I2CHandle1) {
121
        // X-skin: X9=PB6=SCL, X10=PB7=SDA
122
123
        pins[0] = &pin_B6;
        pins[1] = &pin_B7;
124
125
126
        GPIO_InitStructure.Alternate = GPIO_AF4_I2C1;
        // enable the I2C clock
        __I2C1_CLK_ENABLE();
127
#endif
128
    } else if (i2c == &I2CHandle2) {
129
        // Y-skin: Y9=PB10=SCL, Y10=PB11=SDA
130
131
        pins[0] = &pin_B10;
        pins[1] = &pin_B11;
132
133
134
        GPIO_InitStructure.Alternate = GPIO_AF4_I2C2;
        // enable the I2C clock
        __I2C2_CLK_ENABLE();
135
136
137
    } else {
        // I2C does not exist for this board (shouldn't get here, should be checked by caller)
        return;
138
139
    }

140
141
142
143
144
145
    // init the GPIO lines
    for (uint i = 0; i < 2; i++) {
        GPIO_InitStructure.Pin = pins[i]->pin_mask;
        HAL_GPIO_Init(pins[i]->gpio, &GPIO_InitStructure);
    }

146
    // init the I2C device
147
    if (HAL_I2C_Init(i2c) != HAL_OK) {
148
        // init error
149
150
        // TODO should raise an exception, but this function is not necessarily going to be
        // called via Python, so may not be properly wrapped in an NLR handler
151
        printf("HardwareError: HAL_I2C_Init failed\n");
152
153
154
155
        return;
    }
}

156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
void i2c_deinit(I2C_HandleTypeDef *i2c) {
    HAL_I2C_DeInit(i2c);
    if (0) {
#if MICROPY_HW_ENABLE_I2C1
    } else if (i2c->Instance == I2C1) {
        __I2C1_FORCE_RESET();
        __I2C1_RELEASE_RESET();
        __I2C1_CLK_DISABLE();
#endif
    } else if (i2c->Instance == I2C2) {
        __I2C2_FORCE_RESET();
        __I2C2_RELEASE_RESET();
        __I2C2_CLK_DISABLE();
    }
}

172
173
174
175
176
/******************************************************************************/
/* Micro Python bindings                                                      */

typedef struct _pyb_i2c_obj_t {
    mp_obj_base_t base;
177
    I2C_HandleTypeDef *i2c;
178
179
} pyb_i2c_obj_t;

180
181
STATIC inline bool in_master_mode(pyb_i2c_obj_t *self) { return self->i2c->Init.OwnAddress1 == PYB_I2C_MASTER_ADDRESS; }

182
183
STATIC const pyb_i2c_obj_t pyb_i2c_obj[] = {
#if MICROPY_HW_ENABLE_I2C1
184
    {{&pyb_i2c_type}, &I2CHandle1},
185
186
187
#else
    {{&pyb_i2c_type}, NULL},
#endif
188
189
    {{&pyb_i2c_type}, &I2CHandle2}
};
190

191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
STATIC void pyb_i2c_print(void (*print)(void *env, const char *fmt, ...), void *env, mp_obj_t self_in, mp_print_kind_t kind) {
    pyb_i2c_obj_t *self = self_in;

    uint i2c_num;
    if (self->i2c->Instance == I2C1) { i2c_num = 1; }
    else { i2c_num = 2; }

    if (self->i2c->State == HAL_I2C_STATE_RESET) {
        print(env, "I2C(%u)", i2c_num);
    } else {
        if (in_master_mode(self)) {
            print(env, "I2C(%u, I2C.MASTER, baudrate=%u)", i2c_num, self->i2c->Init.ClockSpeed);
        } else {
            print(env, "I2C(%u, I2C.SLAVE, addr=0x%02x)", i2c_num, (self->i2c->Instance->OAR1 >> 1) & 0x7f);
        }
    }
}

209
210
211
212
213
214
215
216
/// \method init(mode, *, addr=0x12, baudrate=400000, gencall=False)
///
/// Initialise the I2C bus with the given parameters:
///
///   - `mode` must be either `I2C.MASTER` or `I2C.SLAVE`
///   - `addr` is the 7-bit address (only sensible for a slave)
///   - `baudrate` is the SCL clock rate (only sensible for a master)
///   - `gencall` is whether to support general call mode
217
218
219
220
221
STATIC const mp_arg_t pyb_i2c_init_args[] = {
    { MP_QSTR_mode,     MP_ARG_REQUIRED | MP_ARG_INT, {.u_int = 0} },
    { MP_QSTR_addr,     MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0x12} },
    { MP_QSTR_baudrate, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 400000} },
    { MP_QSTR_gencall,  MP_ARG_KW_ONLY | MP_ARG_BOOL, {.u_bool = false} },
222
};
223
#define PYB_I2C_INIT_NUM_ARGS ARRAY_SIZE(pyb_i2c_init_args)
224
225
226

STATIC mp_obj_t pyb_i2c_init_helper(const pyb_i2c_obj_t *self, uint n_args, const mp_obj_t *args, mp_map_t *kw_args) {
    // parse args
227
228
    mp_arg_val_t vals[PYB_I2C_INIT_NUM_ARGS];
    mp_arg_parse_all(n_args, args, kw_args, PYB_I2C_INIT_NUM_ARGS, pyb_i2c_init_args, vals);
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253

    // set the I2C configuration values
    I2C_InitTypeDef *init = &self->i2c->Init;

    if (vals[0].u_int == PYB_I2C_MASTER) {
        // use a special address to indicate we are a master
        init->OwnAddress1 = PYB_I2C_MASTER_ADDRESS;
    } else {
        init->OwnAddress1 = (vals[1].u_int << 1) & 0xfe;
    }

    init->AddressingMode  = I2C_ADDRESSINGMODE_7BIT;
    init->ClockSpeed      = MIN(vals[2].u_int, 400000);
    init->DualAddressMode = I2C_DUALADDRESS_DISABLED;
    init->DutyCycle       = I2C_DUTYCYCLE_16_9;
    init->GeneralCallMode = vals[3].u_bool ? I2C_GENERALCALL_ENABLED : I2C_GENERALCALL_DISABLED;
    init->NoStretchMode   = I2C_NOSTRETCH_DISABLED;
    init->OwnAddress2     = 0xfe; // unused

    // init the I2C bus
    i2c_init(self->i2c);

    return mp_const_none;
}

254
255
256
257
258
259
260
/// \classmethod \constructor(bus, ...)
///
/// Construct an I2C object on the given bus.  `bus` can be 1 or 2.
/// With no additional parameters, the I2C 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.
261
262
STATIC mp_obj_t pyb_i2c_make_new(mp_obj_t type_in, uint n_args, uint n_kw, const mp_obj_t *args) {
    // check arguments
263
    mp_arg_check_num(n_args, n_kw, 1, MP_OBJ_FUN_ARGS_MAX, true);
264
265
266
267
268

    // get i2c number
    machine_int_t i2c_id = mp_obj_get_int(args[0]) - 1;

    // check i2c number
269
    if (!(0 <= i2c_id && i2c_id < ARRAY_SIZE(pyb_i2c_obj) && pyb_i2c_obj[i2c_id].i2c != NULL)) {
270
        nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "I2C bus %d does not exist", i2c_id + 1));
271
272
    }

273
    // get I2C object
274
    const pyb_i2c_obj_t *i2c_obj = &pyb_i2c_obj[i2c_id];
275

276
277
278
279
280
281
    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_i2c_init_helper(i2c_obj, n_args - 1, args + 1, &kw_args);
    }
282

283
    return (mp_obj_t)i2c_obj;
284
285
}

286
287
288
289
290
STATIC mp_obj_t pyb_i2c_init(uint n_args, const mp_obj_t *args, mp_map_t *kw_args) {
    return pyb_i2c_init_helper(args[0], n_args - 1, args + 1, kw_args);
}
STATIC MP_DEFINE_CONST_FUN_OBJ_KW(pyb_i2c_init_obj, 1, pyb_i2c_init);

291
292
/// \method deinit()
/// Turn off the I2C bus.
293
294
295
296
297
298
299
STATIC mp_obj_t pyb_i2c_deinit(mp_obj_t self_in) {
    pyb_i2c_obj_t *self = self_in;
    i2c_deinit(self->i2c);
    return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(pyb_i2c_deinit_obj, pyb_i2c_deinit);

300
301
/// \method is_ready(addr)
/// Check if an I2C device responds to the given address.  Only valid when in master mode.
302
303
STATIC mp_obj_t pyb_i2c_is_ready(mp_obj_t self_in, mp_obj_t i2c_addr_o) {
    pyb_i2c_obj_t *self = self_in;
304
305
306
307
308

    if (!in_master_mode(self)) {
        nlr_raise(mp_obj_new_exception_msg(&mp_type_TypeError, "I2C must be a master"));
    }

309
310
311
    machine_uint_t i2c_addr = mp_obj_get_int(i2c_addr_o) << 1;

    for (int i = 0; i < 10; i++) {
312
        HAL_StatusTypeDef status = HAL_I2C_IsDeviceReady(self->i2c, i2c_addr, 10, 200);
313
314
315
316
317
318
319
320
321
        if (status == HAL_OK) {
            return mp_const_true;
        }
    }

    return mp_const_false;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_2(pyb_i2c_is_ready_obj, pyb_i2c_is_ready);

322
323
324
/// \method scan()
/// Scan all I2C addresses from 0x01 to 0x7f and return a list of those that respond.
/// Only valid when in master mode.
325
326
327
STATIC mp_obj_t pyb_i2c_scan(mp_obj_t self_in) {
    pyb_i2c_obj_t *self = self_in;

328
329
330
331
    if (!in_master_mode(self)) {
        nlr_raise(mp_obj_new_exception_msg(&mp_type_TypeError, "I2C must be a master"));
    }

332
333
334
335
    mp_obj_t list = mp_obj_new_list(0, NULL);

    for (uint addr = 1; addr <= 127; addr++) {
        for (int i = 0; i < 10; i++) {
336
            HAL_StatusTypeDef status = HAL_I2C_IsDeviceReady(self->i2c, addr << 1, 10, 200);
337
338
339
340
341
342
343
344
345
346
347
            if (status == HAL_OK) {
                mp_obj_list_append(list, mp_obj_new_int(addr));
                break;
            }
        }
    }

    return list;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(pyb_i2c_scan_obj, pyb_i2c_scan);

348
349
350
351
352
353
354
355
/// \method send(send, addr=0x00, timeout=5000)
/// Send data on the bus:
///
///   - `send` is the data to send (an integer to send, or a buffer object)
///   - `addr` is the address to send to (only required in master mode)
///   - `timeout` is the timeout in milliseconds to wait for the send
///
/// Return value: `None`.
356
357
358
359
STATIC const mp_arg_t pyb_i2c_send_args[] = {
    { MP_QSTR_send,    MP_ARG_REQUIRED | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
    { MP_QSTR_addr,    MP_ARG_INT, {.u_int = PYB_I2C_MASTER_ADDRESS} },
    { MP_QSTR_timeout, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 5000} },
360
};
361
#define PYB_I2C_SEND_NUM_ARGS ARRAY_SIZE(pyb_i2c_send_args)
362

363
364
365
366
STATIC mp_obj_t pyb_i2c_send(uint n_args, const mp_obj_t *args, mp_map_t *kw_args) {
    pyb_i2c_obj_t *self = args[0];

    // parse args
367
368
    mp_arg_val_t vals[PYB_I2C_SEND_NUM_ARGS];
    mp_arg_parse_all(n_args - 1, args + 1, kw_args, PYB_I2C_SEND_NUM_ARGS, pyb_i2c_send_args, vals);
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385

    // get the buffer to send from
    mp_buffer_info_t bufinfo;
    uint8_t data[1];
    pyb_buf_get_for_send(vals[0].u_obj, &bufinfo, data);

    // send the data
    HAL_StatusTypeDef status;
    if (in_master_mode(self)) {
        if (vals[1].u_int == PYB_I2C_MASTER_ADDRESS) {
            nlr_raise(mp_obj_new_exception_msg(&mp_type_TypeError, "addr argument required"));
        }
        machine_uint_t i2c_addr = vals[1].u_int << 1;
        status = HAL_I2C_Master_Transmit(self->i2c, i2c_addr, bufinfo.buf, bufinfo.len, vals[2].u_int);
    } else {
        status = HAL_I2C_Slave_Transmit(self->i2c, bufinfo.buf, bufinfo.len, vals[2].u_int);
    }
386
387
388

    if (status != HAL_OK) {
        // TODO really need a HardwareError object, or something
389
        nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_Exception, "HAL_I2C_xxx_Transmit failed with code %d", status));
390
391
    }

392
    return mp_const_none;
393
}
394
395
STATIC MP_DEFINE_CONST_FUN_OBJ_KW(pyb_i2c_send_obj, 1, pyb_i2c_send);

396
/// \method recv(recv, addr=0x00, timeout=5000)
397
398
399
400
401
402
403
404
405
406
///
/// Receive data on the bus:
///
///   - `recv` can be an integer, which is the number of bytes to receive,
///     or a mutable buffer, which will be filled with received bytes
///   - `addr` is the address to receive from (only required in master mode)
///   - `timeout` is the timeout in milliseconds to wait for the receive
///
/// Return value: if `recv` is an integer then a new buffer of the bytes received,
/// otherwise the same buffer that was passed in to `recv`.
407
408
409
410
STATIC const mp_arg_t pyb_i2c_recv_args[] = {
    { MP_QSTR_recv,    MP_ARG_REQUIRED | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
    { MP_QSTR_addr,    MP_ARG_INT, {.u_int = PYB_I2C_MASTER_ADDRESS} },
    { MP_QSTR_timeout, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 5000} },
411
};
412
#define PYB_I2C_RECV_NUM_ARGS ARRAY_SIZE(pyb_i2c_recv_args)
413

414
415
STATIC mp_obj_t pyb_i2c_recv(uint n_args, const mp_obj_t *args, mp_map_t *kw_args) {
    pyb_i2c_obj_t *self = args[0];
416

417
    // parse args
418
419
    mp_arg_val_t vals[PYB_I2C_RECV_NUM_ARGS];
    mp_arg_parse_all(n_args - 1, args + 1, kw_args, PYB_I2C_RECV_NUM_ARGS, pyb_i2c_recv_args, vals);
420
421
422
423
424
425

    // get the buffer to receive into
    mp_buffer_info_t bufinfo;
    mp_obj_t o_ret = pyb_buf_get_for_recv(vals[0].u_obj, &bufinfo);

    // receive the data
426
    HAL_StatusTypeDef status;
427
428
429
430
431
432
    if (in_master_mode(self)) {
        if (vals[1].u_int == PYB_I2C_MASTER_ADDRESS) {
            nlr_raise(mp_obj_new_exception_msg(&mp_type_TypeError, "addr argument required"));
        }
        machine_uint_t i2c_addr = vals[1].u_int << 1;
        status = HAL_I2C_Master_Receive(self->i2c, i2c_addr, bufinfo.buf, bufinfo.len, vals[2].u_int);
433
    } else {
434
        status = HAL_I2C_Slave_Receive(self->i2c, bufinfo.buf, bufinfo.len, vals[2].u_int);
435
436
437
438
    }

    if (status != HAL_OK) {
        // TODO really need a HardwareError object, or something
439
        nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_Exception, "HAL_I2C_xxx_Receive failed with code %d", status));
440
441
    }

442
443
444
445
446
447
    // return the received data
    if (o_ret == MP_OBJ_NULL) {
        return vals[0].u_obj;
    } else {
        return mp_obj_str_builder_end(o_ret);
    }
448
}
449
STATIC MP_DEFINE_CONST_FUN_OBJ_KW(pyb_i2c_recv_obj, 1, pyb_i2c_recv);
450

451
452
453
454
455
456
457
458
459
460
461
/// \method mem_read(data, addr, memaddr, timeout=5000)
///
/// Read from the memory of an I2C device:
///
///   - `data` can be an integer or a buffer to read into
///   - `addr` is the I2C device address
///   - `memaddr` is the memory location within the I2C device
///   - `timeout` is the timeout in milliseconds to wait for the read
///
/// Returns the read data.
/// This is only valid in master mode.
462
463
464
465
466
STATIC const mp_arg_t pyb_i2c_mem_read_args[] = {
    { MP_QSTR_data,    MP_ARG_REQUIRED | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
    { MP_QSTR_addr,    MP_ARG_REQUIRED | MP_ARG_INT, {.u_int = 0} },
    { MP_QSTR_memaddr, MP_ARG_REQUIRED | MP_ARG_INT, {.u_int = 0} },
    { MP_QSTR_timeout, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 5000} },
467
};
468
#define PYB_I2C_MEM_READ_NUM_ARGS ARRAY_SIZE(pyb_i2c_mem_read_args)
469

470
STATIC mp_obj_t pyb_i2c_mem_read(uint n_args, const mp_obj_t *args, mp_map_t *kw_args) {
471
472
    pyb_i2c_obj_t *self = args[0];

473
474
475
476
477
    if (!in_master_mode(self)) {
        nlr_raise(mp_obj_new_exception_msg(&mp_type_TypeError, "I2C must be a master"));
    }

    // parse args
478
479
    mp_arg_val_t vals[PYB_I2C_MEM_READ_NUM_ARGS];
    mp_arg_parse_all(n_args - 1, args + 1, kw_args, PYB_I2C_MEM_READ_NUM_ARGS, pyb_i2c_mem_read_args, vals);
480
481
482
483

    // get the buffer to read into
    mp_buffer_info_t bufinfo;
    mp_obj_t o_ret = pyb_buf_get_for_recv(vals[0].u_obj, &bufinfo);
484

485
486
487
488
489
    // get the addresses
    machine_uint_t i2c_addr = vals[1].u_int << 1;
    machine_uint_t mem_addr = vals[2].u_int;

    HAL_StatusTypeDef status = HAL_I2C_Mem_Read(self->i2c, i2c_addr, mem_addr, I2C_MEMADD_SIZE_8BIT, bufinfo.buf, bufinfo.len, vals[3].u_int);
490
491
492

    if (status != HAL_OK) {
        // TODO really need a HardwareError object, or something
493
        nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_Exception, "HAL_I2C_Mem_Read failed with code %d", status));
494
495
    }

496
497
498
499
500
501
    // return the read data
    if (o_ret == MP_OBJ_NULL) {
        return vals[0].u_obj;
    } else {
        return mp_obj_str_builder_end(o_ret);
    }
502
}
503
STATIC MP_DEFINE_CONST_FUN_OBJ_KW(pyb_i2c_mem_read_obj, 1, pyb_i2c_mem_read);
504

505
506
507
508
509
510
511
512
513
514
515
/// \method mem_write(data, addr, memaddr, timeout=5000)
///
/// Write to the memory of an I2C device:
///
///   - `data` can be an integer or a buffer to write from
///   - `addr` is the I2C device address
///   - `memaddr` is the memory location within the I2C device
///   - `timeout` is the timeout in milliseconds to wait for the write
///
/// Returns `None`.
/// This is only valid in master mode.
516
STATIC mp_obj_t pyb_i2c_mem_write(uint n_args, const mp_obj_t *args, mp_map_t *kw_args) {
517
    pyb_i2c_obj_t *self = args[0];
518
519
520

    if (!in_master_mode(self)) {
        nlr_raise(mp_obj_new_exception_msg(&mp_type_TypeError, "I2C must be a master"));
521
522
    }

523
    // parse args (same as mem_read)
524
525
    mp_arg_val_t vals[PYB_I2C_MEM_READ_NUM_ARGS];
    mp_arg_parse_all(n_args - 1, args + 1, kw_args, PYB_I2C_MEM_READ_NUM_ARGS, pyb_i2c_mem_read_args, vals);
526
527
528
529
530
531
532
533
534
535
536

    // get the buffer to write from
    mp_buffer_info_t bufinfo;
    uint8_t data[1];
    pyb_buf_get_for_send(vals[0].u_obj, &bufinfo, data);

    // get the addresses
    machine_uint_t i2c_addr = vals[1].u_int << 1;
    machine_uint_t mem_addr = vals[2].u_int;

    HAL_StatusTypeDef status = HAL_I2C_Mem_Write(self->i2c, i2c_addr, mem_addr, I2C_MEMADD_SIZE_8BIT, bufinfo.buf, bufinfo.len, vals[3].u_int);
537
538
539

    if (status != HAL_OK) {
        // TODO really need a HardwareError object, or something
540
        nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_Exception, "HAL_I2C_Mem_Write failed with code %d", status));
541
542
543
544
    }

    return mp_const_none;
}
545
STATIC MP_DEFINE_CONST_FUN_OBJ_KW(pyb_i2c_mem_write_obj, 1, pyb_i2c_mem_write);
546

547
STATIC const mp_map_elem_t pyb_i2c_locals_dict_table[] = {
548
549
550
    // instance methods
    { MP_OBJ_NEW_QSTR(MP_QSTR_init), (mp_obj_t)&pyb_i2c_init_obj },
    { MP_OBJ_NEW_QSTR(MP_QSTR_deinit), (mp_obj_t)&pyb_i2c_deinit_obj },
551
    { MP_OBJ_NEW_QSTR(MP_QSTR_is_ready), (mp_obj_t)&pyb_i2c_is_ready_obj },
552
    { MP_OBJ_NEW_QSTR(MP_QSTR_scan), (mp_obj_t)&pyb_i2c_scan_obj },
553
554
    { MP_OBJ_NEW_QSTR(MP_QSTR_send), (mp_obj_t)&pyb_i2c_send_obj },
    { MP_OBJ_NEW_QSTR(MP_QSTR_recv), (mp_obj_t)&pyb_i2c_recv_obj },
555
556
    { MP_OBJ_NEW_QSTR(MP_QSTR_mem_read), (mp_obj_t)&pyb_i2c_mem_read_obj },
    { MP_OBJ_NEW_QSTR(MP_QSTR_mem_write), (mp_obj_t)&pyb_i2c_mem_write_obj },
557
558

    // class constants
559
560
    /// \constant MASTER - for initialising the bus to master mode
    /// \constant SLAVE - for initialising the bus to slave mode
561
562
    { MP_OBJ_NEW_QSTR(MP_QSTR_MASTER),       MP_OBJ_NEW_SMALL_INT(PYB_I2C_MASTER) },
    { MP_OBJ_NEW_QSTR(MP_QSTR_SLAVE),        MP_OBJ_NEW_SMALL_INT(PYB_I2C_SLAVE) },
563
564
};

565
566
STATIC MP_DEFINE_CONST_DICT(pyb_i2c_locals_dict, pyb_i2c_locals_dict_table);

567
568
569
const mp_obj_type_t pyb_i2c_type = {
    { &mp_type_type },
    .name = MP_QSTR_I2C,
570
    .print = pyb_i2c_print,
571
    .make_new = pyb_i2c_make_new,
572
    .locals_dict = (mp_obj_t)&pyb_i2c_locals_dict,
573
};