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rp2/machine_i2c_target: Implement I2CTargetMemory.
Signed-off-by: Damien George <[email protected]>
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‎ports/rp2/CMakeLists.txt‎

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@@ -233,6 +233,7 @@ set(PICO_SDK_COMPONENTS
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pico_binary_info
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pico_bootrom
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pico_flash
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pico_i2c_slave
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pico_multicore
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pico_platform
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pico_platform_compiler

‎ports/rp2/machine_i2c_target.c‎

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/*
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* This file is part of the MicroPython project, http://micropython.org/
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*
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* The MIT License (MIT)
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*
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* Copyright (c) 2025 Damien P. George
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy
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* of this software and associated documentation files (the "Software"), to deal
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* in the Software without restriction, including without limitation the rights
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* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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* copies of the Software, and to permit persons to whom the Software is
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* furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in
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* all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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* THE SOFTWARE.
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*/
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// This file is never compiled standalone, it's included directly from
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// extmod/machine_i2c_target.c via MICROPY_PY_MACHINE_I2C_TARGET_INCLUDEFILE.
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#include "pico/i2c_slave.h"
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// TODO: should be in a common i2c header
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#ifdef MICROPY_HW_I2C_NO_DEFAULT_PINS
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// With no default I2C, need to require the pin args.
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#define MICROPY_HW_I2C0_SCL (0)
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#define MICROPY_HW_I2C0_SDA (0)
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#define MICROPY_HW_I2C1_SCL (0)
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#define MICROPY_HW_I2C1_SDA (0)
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#define MICROPY_I2C_PINS_ARG_OPTS MP_ARG_REQUIRED
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#else
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// Most boards do not require pin args.
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#define MICROPY_I2C_PINS_ARG_OPTS 0
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#ifndef MICROPY_HW_I2C0_SCL
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#if PICO_DEFAULT_I2C == 0
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#define MICROPY_HW_I2C0_SCL (PICO_DEFAULT_I2C_SCL_PIN)
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#define MICROPY_HW_I2C0_SDA (PICO_DEFAULT_I2C_SDA_PIN)
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#else
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#define MICROPY_HW_I2C0_SCL (9)
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#define MICROPY_HW_I2C0_SDA (8)
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#endif
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#endif
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#ifndef MICROPY_HW_I2C1_SCL
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#if PICO_DEFAULT_I2C == 1
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#define MICROPY_HW_I2C1_SCL (PICO_DEFAULT_I2C_SCL_PIN)
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#define MICROPY_HW_I2C1_SDA (PICO_DEFAULT_I2C_SDA_PIN)
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#else
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#define MICROPY_HW_I2C1_SCL (7)
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#define MICROPY_HW_I2C1_SDA (6)
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#endif
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#endif
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#endif
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// SDA/SCL on even/odd pins, I2C0/I2C1 on even/odd pairs of pins.
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// TODO: should be in a common i2c header
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#define IS_VALID_SCL(i2c, pin) (((pin) & 1) == 1 && (((pin) & 2) >> 1) == (i2c))
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#define IS_VALID_SDA(i2c, pin) (((pin) & 1) == 0 && (((pin) & 2) >> 1) == (i2c))
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typedef struct _machine_i2c_target_obj_t {
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mp_obj_base_t base;
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i2c_inst_t *const i2c_inst;
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mp_hal_pin_obj_t scl;
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mp_hal_pin_obj_t sda;
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} machine_i2c_target_obj_t;
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static machine_i2c_target_data_t i2c_target_data[4];
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static machine_i2c_target_obj_t machine_i2c_target_obj[] = {
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{{&machine_i2c_target_type}, i2c0, MICROPY_HW_I2C0_SCL, MICROPY_HW_I2C0_SDA},
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{{&machine_i2c_target_type}, i2c1, MICROPY_HW_I2C1_SCL, MICROPY_HW_I2C1_SDA},
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};
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/******************************************************************************/
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// pico-sdk bindings
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static void i2c_target_handler(i2c_inst_t *i2c, i2c_slave_event_t event) {
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unsigned int i2c_id = i2c == i2c0 ? 0 : 1;
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machine_i2c_target_obj_t *self = &machine_i2c_target_obj[i2c_id];
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machine_i2c_target_data_t *data = &i2c_target_data[i2c_id];
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switch (event) {
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// Data from controller is available for reading.
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case I2C_SLAVE_RECEIVE:
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if (data->state == STATE_IDLE) {
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machine_i2c_target_data_addr_match(data, false);
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}
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machine_i2c_target_data_write_request(self, data);
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break;
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// Controller is requesting data.
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case I2C_SLAVE_REQUEST: {
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if (data->state == STATE_IDLE) {
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machine_i2c_target_data_addr_match(data, true);
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}
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//i2c_write_byte_raw(i2c, 0x12);
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//break;
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machine_i2c_target_data_read_request(self, data);
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break;
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}
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// Controller has sent a Stop or Restart signal.
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case I2C_SLAVE_FINISH:
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// TODO handle the fact this could be a restart
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machine_i2c_target_data_restart_or_stop(data);
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break;
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}
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}
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/******************************************************************************/
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// I2CTarget port implementation
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static void mp_machine_i2c_target_deinit_all_port(void) {
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}
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static void mp_machine_i2c_target_event_callback(machine_i2c_target_irq_obj_t *irq) {
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mp_irq_handler(&irq->base);
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}
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static mp_int_t mp_machine_i2c_target_read_bytes(machine_i2c_target_obj_t *self, size_t len, uint8_t *buf) {
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i2c_hw_t *i2c_hw = i2c_get_hw(self->i2c_inst);
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mp_int_t i = 0;
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while (i < len && i2c_hw->status & I2C_IC_STATUS_RFNE_BITS) {
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buf[i++] = i2c_read_byte_raw(self->i2c_inst);
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}
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return i;
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}
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static mp_int_t mp_machine_i2c_target_write_bytes(machine_i2c_target_obj_t *self, size_t len, const uint8_t *buf) {
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i2c_write_byte_raw(self->i2c_inst, buf[0]);
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return 1;
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}
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static void mp_machine_i2c_target_irq_config(machine_i2c_target_obj_t *self, unsigned int trigger) {
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}
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static mp_obj_t mp_machine_i2c_target_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *all_args) {
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// TODO: reconsider order of arguments
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enum { ARG_id, ARG_addr, ARG_addrsize, ARG_mem, ARG_mem_addrsize, ARG_scl, ARG_sda };
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static const mp_arg_t allowed_args[] = {
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#ifdef PICO_DEFAULT_I2C
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{ MP_QSTR_id, MP_ARG_INT, {.u_int = PICO_DEFAULT_I2C} },
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#else
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{ MP_QSTR_id, MP_ARG_INT | MP_ARG_REQUIRED },
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#endif
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{ MP_QSTR_addr, MP_ARG_REQUIRED | MP_ARG_INT },
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{ MP_QSTR_addrsize, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 7} },
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{ MP_QSTR_mem, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_rom_obj = MP_ROM_NONE} },
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{ MP_QSTR_mem_addrsize, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 8} },
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{ MP_QSTR_scl, MICROPY_I2C_PINS_ARG_OPTS | MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_rom_obj = MP_ROM_NONE} },
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{ MP_QSTR_sda, MICROPY_I2C_PINS_ARG_OPTS | MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_rom_obj = MP_ROM_NONE} },
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};
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// Parse args.
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mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
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mp_arg_parse_all_kw_array(n_args, n_kw, all_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
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int i2c_id = args[ARG_id].u_int;
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// Check if the I2C bus is valid
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if (i2c_id < 0 || i2c_id >= MP_ARRAY_SIZE(machine_i2c_target_obj)) {
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mp_raise_msg_varg(&mp_type_ValueError, MP_ERROR_TEXT("I2C(%d) doesn't exist"), i2c_id);
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}
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// Get static peripheral object.
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machine_i2c_target_obj_t *self = &machine_i2c_target_obj[i2c_id];
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// Initialise data.
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MP_STATE_PORT(i2c_target_mem_obj)[i2c_id] = args[ARG_mem].u_obj;
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machine_i2c_target_data_t *data = &i2c_target_data[i2c_id];
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machine_i2c_target_data_init(data, args[ARG_mem].u_obj, args[ARG_mem_addrsize].u_int);
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// Set SCL/SDA pins if configured.
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if (args[ARG_scl].u_obj != mp_const_none) {
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int scl = mp_hal_get_pin_obj(args[ARG_scl].u_obj);
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if (!IS_VALID_SCL(i2c_id, scl)) {
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mp_raise_ValueError(MP_ERROR_TEXT("bad SCL pin"));
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}
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self->scl = scl;
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}
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if (args[ARG_sda].u_obj != mp_const_none) {
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int sda = mp_hal_get_pin_obj(args[ARG_sda].u_obj);
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if (!IS_VALID_SDA(i2c_id, sda)) {
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mp_raise_ValueError(MP_ERROR_TEXT("bad SDA pin"));
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}
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self->sda = sda;
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}
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// Initialise the I2C target.
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// TODO: don't reinitialize if no arguments given.
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i2c_slave_init(self->i2c_inst, args[ARG_addr].u_int, i2c_target_handler);
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gpio_set_function(self->scl, GPIO_FUNC_I2C);
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gpio_set_function(self->sda, GPIO_FUNC_I2C);
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gpio_set_pulls(self->scl, true, 0);
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gpio_set_pulls(self->sda, true, 0);
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return MP_OBJ_FROM_PTR(self);
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}
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static void mp_machine_i2c_target_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t kind) {
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machine_i2c_target_obj_t *self = MP_OBJ_TO_PTR(self_in);
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i2c_hw_t *i2c_hw = i2c_get_hw(self->i2c_inst);
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mp_printf(print, "I2CTarget(%u, addr=%u, scl=%u, sda=%u)",
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self - &machine_i2c_target_obj[0], i2c_hw->sar, self->scl, self->sda);
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}
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static void mp_machine_i2c_target_deinit(machine_i2c_target_obj_t *self) {
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i2c_slave_deinit(self->i2c_inst);
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}

‎ports/rp2/mpconfigport.h‎

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#define MICROPY_PY_MACHINE_PWM (1)
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#define MICROPY_PY_MACHINE_PWM_INCLUDEFILE "ports/rp2/machine_pwm.c"
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#define MICROPY_PY_MACHINE_I2C (1)
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#define MICROPY_PY_MACHINE_I2C_TARGET (1)
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#define MICROPY_PY_MACHINE_I2C_TARGET_INCLUDEFILE "ports/rp2/machine_i2c_target.c"
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#define MICROPY_PY_MACHINE_SOFTI2C (1)
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#define MICROPY_PY_MACHINE_I2S (1)
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#define MICROPY_PY_MACHINE_I2S_INCLUDEFILE "ports/rp2/machine_i2s.c"

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