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-rw-r--r--shared-module/bitbangio/I2C.c210
-rw-r--r--shared-module/bitbangio/SPI.c167
-rw-r--r--shared-module/bitbangio/__init__.c27
-rw-r--r--shared-module/bitbangio/types.h51
4 files changed, 455 insertions, 0 deletions
diff --git a/shared-module/bitbangio/I2C.c b/shared-module/bitbangio/I2C.c
new file mode 100644
index 000000000..bab5074b4
--- /dev/null
+++ b/shared-module/bitbangio/I2C.c
@@ -0,0 +1,210 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2016 Damien P. George, Scott Shawcroft
+ *
+ * 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 "shared-bindings/bitbangio/I2C.h"
+
+#include "py/obj.h"
+
+#include "common-hal/microcontroller/types.h"
+#include "shared-bindings/microcontroller/__init__.h"
+#include "shared-bindings/nativeio/DigitalInOut.h"
+#include "shared-module/bitbangio/types.h"
+
+#define I2C_STRETCH_LIMIT 255
+
+STATIC void delay(bitbangio_i2c_obj_t *self) {
+ // We need to use an accurate delay to get acceptable I2C
+ // speeds (eg 1us should be not much more than 1us).
+ common_hal_mcu_delay_us(self->us_delay);
+}
+
+STATIC void scl_low(bitbangio_i2c_obj_t *self) {
+ common_hal_nativeio_digitalinout_set_value(&self->scl, false);
+}
+
+STATIC void scl_release(bitbangio_i2c_obj_t *self) {
+ common_hal_nativeio_digitalinout_set_value(&self->scl, true);
+ delay(self);
+ // For clock stretching, wait for the SCL pin to be released, with timeout.
+ for (int count = I2C_STRETCH_LIMIT; !common_hal_nativeio_digitalinout_get_value(&self->scl) && count; --count) {
+ common_hal_mcu_delay_us(1);
+ }
+}
+
+STATIC void sda_low(bitbangio_i2c_obj_t *self) {
+ common_hal_nativeio_digitalinout_set_value(&self->sda, false);
+}
+
+STATIC void sda_release(bitbangio_i2c_obj_t *self) {
+ common_hal_nativeio_digitalinout_set_value(&self->sda, true);
+}
+
+STATIC bool sda_read(bitbangio_i2c_obj_t *self) {
+ common_hal_nativeio_digitalinout_switch_to_input(&self->sda, PULL_UP);
+ bool value = common_hal_nativeio_digitalinout_get_value(&self->sda);
+ common_hal_nativeio_digitalinout_switch_to_output(&self->sda, true, DRIVE_MODE_OPEN_DRAIN);
+ return value;
+}
+
+STATIC void start(bitbangio_i2c_obj_t *self) {
+ sda_release(self);
+ delay(self);
+ scl_release(self);
+ sda_low(self);
+ delay(self);
+}
+
+STATIC void stop(bitbangio_i2c_obj_t *self) {
+ delay(self);
+ sda_low(self);
+ delay(self);
+ scl_release(self);
+ sda_release(self);
+ delay(self);
+}
+
+STATIC int write_byte(bitbangio_i2c_obj_t *self, uint8_t val) {
+ delay(self);
+ scl_low(self);
+
+ for (int i = 7; i >= 0; i--) {
+ if ((val >> i) & 1) {
+ sda_release(self);
+ } else {
+ sda_low(self);
+ }
+ delay(self);
+ scl_release(self);
+ scl_low(self);
+ }
+
+ sda_release(self);
+ delay(self);
+ scl_release(self);
+
+ int ret = sda_read(self);
+ delay(self);
+ scl_low(self);
+
+ return !ret;
+}
+
+STATIC bool read_byte(bitbangio_i2c_obj_t *self, uint8_t *val, bool ack) {
+ delay(self);
+ scl_low(self);
+ delay(self);
+
+ uint8_t data = 0;
+ for (int i = 7; i >= 0; i--) {
+ scl_release(self);
+ data = (data << 1) | sda_read(self);
+ scl_low(self);
+ delay(self);
+ }
+ *val = data;
+
+ // send ack/nack bit
+ if (ack) {
+ sda_low(self);
+ }
+ delay(self);
+ scl_release(self);
+ scl_low(self);
+ sda_release(self);
+
+ return true;
+}
+
+void shared_module_bitbangio_i2c_construct(bitbangio_i2c_obj_t *self,
+ const mcu_pin_obj_t * scl,
+ const mcu_pin_obj_t * sda,
+ uint32_t freq) {
+ self->us_delay = 500000 / freq;
+ if (self->us_delay == 0) {
+ self->us_delay = 1;
+ }
+ digitalinout_result_t result = common_hal_nativeio_digitalinout_construct(&self->scl, scl);
+ if (result != DIGITALINOUT_OK) {
+ return;
+ }
+ result = common_hal_nativeio_digitalinout_construct(&self->sda, sda);
+ if (result != DIGITALINOUT_OK) {
+ common_hal_nativeio_digitalinout_deinit(&self->scl);
+ return;
+ }
+ common_hal_nativeio_digitalinout_switch_to_output(&self->scl, true, DRIVE_MODE_OPEN_DRAIN);
+ common_hal_nativeio_digitalinout_switch_to_output(&self->sda, true, DRIVE_MODE_OPEN_DRAIN);
+
+ stop(self);
+}
+
+void shared_module_bitbangio_i2c_deinit(bitbangio_i2c_obj_t *self) {
+ common_hal_nativeio_digitalinout_deinit(&self->scl);
+ common_hal_nativeio_digitalinout_deinit(&self->sda);
+}
+
+bool shared_module_bitbangio_i2c_probe(bitbangio_i2c_obj_t *self, uint8_t addr) {
+ start(self);
+ bool ok = write_byte(self, addr << 1);
+ stop(self);
+ return ok;
+}
+
+bool shared_module_bitbangio_i2c_write(bitbangio_i2c_obj_t *self, uint16_t addr,
+ const uint8_t *data, size_t len, bool transmit_stop_bit) {
+ // start the I2C transaction
+ start(self);
+ bool ok = write_byte(self, addr << 1);
+
+ for (uint32_t i = 0; i < len; i++) {
+ ok = ok && write_byte(self, data[i]);
+ if (!ok) {
+ break;
+ }
+ }
+
+ if (transmit_stop_bit) {
+ stop(self);
+ }
+ return ok;
+}
+
+bool shared_module_bitbangio_i2c_read(bitbangio_i2c_obj_t *self, uint16_t addr,
+ uint8_t * data, size_t len) {
+ // start the I2C transaction
+ start(self);
+ bool ok = write_byte(self, (addr << 1) | 1);
+
+ for (uint32_t i = 0; i < len; i++) {
+ ok = ok && read_byte(self, data + i, i < len - 1);
+ if (!ok) {
+ break;
+ }
+ }
+
+ stop(self);
+ return ok;
+}
diff --git a/shared-module/bitbangio/SPI.c b/shared-module/bitbangio/SPI.c
new file mode 100644
index 000000000..5d77efaf9
--- /dev/null
+++ b/shared-module/bitbangio/SPI.c
@@ -0,0 +1,167 @@
+/*
+ * This file is part of the MicroPython 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.
+ */
+
+#include "mpconfigport.h"
+
+#include "py/obj.h"
+
+#include "common-hal/microcontroller/types.h"
+#include "shared-bindings/microcontroller/__init__.h"
+#include "shared-bindings/nativeio/DigitalInOut.h"
+#include "shared-module/bitbangio/types.h"
+
+#define MAX_BAUDRATE (common_hal_mcu_get_clock_frequency() / 48)
+
+extern void shared_module_bitbangio_spi_construct(bitbangio_spi_obj_t *self,
+ const mcu_pin_obj_t * clock, const mcu_pin_obj_t * mosi,
+ const mcu_pin_obj_t * miso, uint32_t baudrate) {
+ digitalinout_result_t result = common_hal_nativeio_digitalinout_construct(&self->clock, clock);
+ if (result != DIGITALINOUT_OK) {
+ return;
+ }
+ result = common_hal_nativeio_digitalinout_construct(&self->mosi, mosi);
+ if (result != DIGITALINOUT_OK) {
+ common_hal_nativeio_digitalinout_deinit(&self->clock);
+ return;
+ }
+ result = common_hal_nativeio_digitalinout_construct(&self->miso, miso);
+ if (result != DIGITALINOUT_OK) {
+ common_hal_nativeio_digitalinout_deinit(&self->clock);
+ common_hal_nativeio_digitalinout_deinit(&self->mosi);
+ return;
+ }
+
+ self->delay_half = 500000 / baudrate;
+ // round delay_half up so that: actual_baudrate <= requested_baudrate
+ if (500000 % baudrate != 0) {
+ self->delay_half += 1;
+ }
+
+ self->polarity = 0;
+ self->phase = 0;
+}
+
+extern void shared_module_bitbangio_spi_deinit(bitbangio_spi_obj_t *self) {
+ common_hal_nativeio_digitalinout_deinit(&self->clock);
+ common_hal_nativeio_digitalinout_deinit(&self->mosi);
+ common_hal_nativeio_digitalinout_deinit(&self->miso);
+}
+
+bool shared_module_bitbangio_spi_transfer(bitbangio_spi_obj_t *self,
+ const uint8_t *write_buffer, size_t write_buffer_len,
+ uint8_t *read_buffer, size_t read_buffer_len) {
+ uint32_t delay_half = self->delay_half;
+
+ // only MSB transfer is implemented
+
+ // If a port defines MICROPY_PY_MACHINE_SPI_MIN_DELAY, and the configured
+ // delay_half is equal to this value, then the software SPI implementation
+ // will run as fast as possible, limited only by CPU speed and GPIO time.
+ #ifdef MICROPY_PY_MACHINE_SPI_MIN_DELAY
+ if (delay_half <= MICROPY_PY_MACHINE_SPI_MIN_DELAY) {
+ for (size_t i = 0; i < write_buffer_len; ++i) {
+ uint8_t data_out = write_buffer[i];
+ for (int j = 0; j < 8; ++j, data_out <<= 1) {
+ common_hal_nativeio_digitalinout_set_value(&self->mosi, (data_out >> 7) & 1);
+ common_hal_nativeio_digitalinout_set_value(&self->clock, 1 - self->polarity);
+ common_hal_nativeio_digitalinout_set_value(&self->clock, self->polarity);
+ }
+ if (dest != NULL) {
+ dest[i] = data_in;
+ }
+ }
+
+ // Clock out zeroes while we read.
+ common_hal_nativeio_digitalinout_set_value(&self->mosi, false);
+ for (size_t i = 0; i < read_buffer_len; ++i) {
+ uint8_t data_in = 0;
+ for (int j = 0; j < 8; ++j, data_out <<= 1) {
+ common_hal_nativeio_digitalinout_set_value(&self->clock, 1 - self->polarity);
+ data_in = (data_in << 1) | common_hal_nativeio_digitalinout_get_value(&self->miso);
+ common_hal_nativeio_digitalinout_set_value(&self->clock, self->polarity);
+ }
+ read_buffer[i] = data_in;
+ }
+ return true;
+ }
+ #endif
+
+ for (size_t i = 0; i < write_buffer_len; ++i) {
+ uint8_t data_out = write_buffer[i];
+ for (int j = 0; j < 8; ++j, data_out <<= 1) {
+ common_hal_nativeio_digitalinout_set_value(&self->mosi, (data_out >> 7) & 1);
+ if (self->phase == 0) {
+ common_hal_mcu_delay_us(delay_half);
+ common_hal_nativeio_digitalinout_set_value(&self->clock, 1 - self->polarity);
+ } else {
+ common_hal_nativeio_digitalinout_set_value(&self->clock, 1 - self->polarity);
+ common_hal_mcu_delay_us(delay_half);
+ }
+ if (self->phase == 0) {
+ common_hal_mcu_delay_us(delay_half);
+ common_hal_nativeio_digitalinout_set_value(&self->clock, self->polarity);
+ } else {
+ common_hal_nativeio_digitalinout_set_value(&self->clock, self->polarity);
+ common_hal_mcu_delay_us(delay_half);
+ }
+ }
+
+ // Some ports need a regular callback, but probably we don't need
+ // to do this every byte, or even at all.
+ #ifdef MICROPY_EVENT_POLL_HOOK
+ MICROPY_EVENT_POLL_HOOK;
+ #endif
+ }
+ common_hal_nativeio_digitalinout_set_value(&self->mosi, false);
+ for (size_t i = 0; i < read_buffer_len; ++i) {
+ uint8_t data_in = 0;
+ for (int j = 0; j < 8; ++j) {
+ if (self->phase == 0) {
+ common_hal_mcu_delay_us(delay_half);
+ common_hal_nativeio_digitalinout_set_value(&self->clock, 1 - self->polarity);
+ } else {
+ common_hal_nativeio_digitalinout_set_value(&self->clock, 1 - self->polarity);
+ common_hal_mcu_delay_us(delay_half);
+ }
+ data_in = (data_in << 1) | common_hal_nativeio_digitalinout_get_value(&self->miso);
+ if (self->phase == 0) {
+ common_hal_mcu_delay_us(delay_half);
+ common_hal_nativeio_digitalinout_set_value(&self->clock, self->polarity);
+ } else {
+ common_hal_nativeio_digitalinout_set_value(&self->clock, self->polarity);
+ common_hal_mcu_delay_us(delay_half);
+ }
+ }
+ read_buffer[i] = data_in;
+
+ // Some ports need a regular callback, but probably we don't need
+ // to do this every byte, or even at all.
+ #ifdef MICROPY_EVENT_POLL_HOOK
+ MICROPY_EVENT_POLL_HOOK;
+ #endif
+ }
+ return true;
+}
diff --git a/shared-module/bitbangio/__init__.c b/shared-module/bitbangio/__init__.c
new file mode 100644
index 000000000..674343c53
--- /dev/null
+++ b/shared-module/bitbangio/__init__.c
@@ -0,0 +1,27 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2016 Scott Shawcroft
+ *
+ * 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.
+ */
+
+// Nothing now.
diff --git a/shared-module/bitbangio/types.h b/shared-module/bitbangio/types.h
new file mode 100644
index 000000000..e6a29ab54
--- /dev/null
+++ b/shared-module/bitbangio/types.h
@@ -0,0 +1,51 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2016 Scott Shawcroft
+ *
+ * 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.
+ */
+
+#ifndef __MICROPY_INCLUDED_SHARED_MODULE_BITBANGIO_TYPES_H__
+#define __MICROPY_INCLUDED_SHARED_MODULE_BITBANGIO_TYPES_H__
+
+#include "common-hal/nativeio/types.h"
+
+#include "py/obj.h"
+
+typedef struct {
+ mp_obj_base_t base;
+ nativeio_digitalinout_obj_t scl;
+ nativeio_digitalinout_obj_t sda;
+ uint32_t us_delay;
+} bitbangio_i2c_obj_t;
+
+typedef struct {
+ mp_obj_base_t base;
+ nativeio_digitalinout_obj_t clock;
+ nativeio_digitalinout_obj_t mosi;
+ nativeio_digitalinout_obj_t miso;
+ uint32_t delay_half;
+ uint8_t polarity;
+ uint8_t phase;
+} bitbangio_spi_obj_t;
+
+#endif // __MICROPY_INCLUDED_SHARED_MODULE_BITBANGIO_TYPES_H__
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