diff --git a/py/runtime.c b/py/runtime.c
index 9da5688763809408c6bb762a4511f4f3392ea1e4..a1bd676367d86482768d5fbe4afc86c854dcfc57 100644
--- a/py/runtime.c
+++ b/py/runtime.c
@@ -319,6 +319,10 @@ static bool fit_small_int(py_small_int_t o) {
return true;
}
+py_obj_t py_obj_new_int(int value) {
+ return TO_SMALL_INT(value);
+}
+
py_obj_t py_obj_new_const(const char *id) {
py_obj_base_t *o = m_new(py_obj_base_t, 1);
o->kind = O_CONST;
diff --git a/py/runtime.h b/py/runtime.h
index 326ca0833bb6f2a68774066fec0020a4682710d9..98d77c8e727172f6ea268db50d53c612981a7417 100644
--- a/py/runtime.h
+++ b/py/runtime.h
@@ -99,6 +99,7 @@ void py_obj_print(py_obj_t o);
int rt_is_true(py_obj_t arg);
int py_get_int(py_obj_t arg);
qstr py_get_qstr(py_obj_t arg);
+py_obj_t py_obj_new_int(int value);
py_obj_t rt_load_const_str(qstr qstr);
py_obj_t rt_load_name(qstr qstr);
py_obj_t rt_load_global(qstr qstr);
diff --git a/stm/main.c b/stm/main.c
index 94c40f27e983145a64ec408719be1012235d9c4f..801a0decd29bb06b557244a9f06ada73c1581e10 100644
--- a/stm/main.c
+++ b/stm/main.c
@@ -433,6 +433,24 @@ py_obj_t pyb_servo_set(py_obj_t value) {
return py_const_none;
}
+#define MMA_ADDR (0x4c)
+
+py_obj_t pyb_mma_read() {
+ mma_start(MMA_ADDR, 1);
+ mma_send_byte(0);
+ mma_restart(MMA_ADDR, 0);
+ py_obj_t data[4];
+ for (int i = 3; i >= 1; i--) {
+ int v = mma_read_ack() & 0x3f;
+ if (v & 0x20) {
+ v |= ~0x1f;
+ }
+ data[i] = py_obj_new_int(v);
+ }
+ data[0] = py_obj_new_int(mma_read_nack());
+ return rt_build_tuple(4, data); // items in reverse order in data
+}
+
int main(void) {
// TODO disable JTAG
@@ -480,6 +498,7 @@ soft_reset:
rt_store_attr(m, qstr_from_str_static("led"), rt_make_function_1(pyb_led));
rt_store_attr(m, qstr_from_str_static("sw"), rt_make_function_0(pyb_sw));
rt_store_attr(m, qstr_from_str_static("servo"), rt_make_function_1(pyb_servo_set));
+ rt_store_attr(m, qstr_from_str_static("mma"), rt_make_function_0(pyb_mma_read));
rt_store_name(qstr_from_str_static("pyb"), m);
}
@@ -554,6 +573,62 @@ soft_reset:
// USB
usb_init();
+ // MMA
+ {
+ // init and reset address to zero
+ mma_init();
+ mma_start(MMA_ADDR, 1);
+ mma_send_byte(0);
+ mma_stop();
+
+ /*
+ // read and print all 11 registers
+ mma_start(MMA_ADDR, 1);
+ mma_send_byte(0);
+ mma_restart(MMA_ADDR, 0);
+ for (int i = 0; i <= 0xa; i++) {
+ int data;
+ if (i == 0xa) {
+ data = mma_read_nack();
+ } else {
+ data = mma_read_ack();
+ }
+ printf(" %02x", data);
+ }
+ printf("\n");
+ */
+
+ // put into active mode
+ mma_start(MMA_ADDR, 1);
+ mma_send_byte(7); // mode
+ mma_send_byte(1); // active mode
+ mma_stop();
+
+ /*
+ // infinite loop to read values
+ for (;;) {
+ sys_tick_delay_ms(500);
+
+ mma_start(MMA_ADDR, 1);
+ mma_send_byte(0);
+ mma_restart(MMA_ADDR, 0);
+ for (int i = 0; i <= 3; i++) {
+ int data;
+ if (i == 3) {
+ data = mma_read_nack();
+ printf(" %02x\n", data);
+ } else {
+ data = mma_read_ack() & 0x3f;
+ if (data & 0x20) {
+ data |= ~0x1f;
+ }
+ printf(" % 2d", data);
+ }
+ }
+ }
+ */
+ }
+
// turn boot-up LED off
led_state(PYB_LED_G1, 0);
@@ -737,60 +812,6 @@ soft_reset:
led_state(PYB_LED_G1, 0);
}
- // MMA testing
- if (0) {
- printf("1");
- mma_init();
- printf("2");
- mma_start(0x4c, 1);
- printf("3");
- mma_send_byte(0);
- printf("4");
- mma_stop();
- printf("5");
- mma_start(0x4c, 1);
- printf("6");
- mma_send_byte(0);
- printf("7");
- mma_restart(0x4c, 0);
- for (int i = 0; i <= 0xa; i++) {
- int data;
- if (i == 0xa) {
- data = mma_read_nack();
- } else {
- data = mma_read_ack();
- }
- printf(" %02x", data);
- }
- printf("\n");
-
- mma_start(0x4c, 1);
- mma_send_byte(7); // mode
- mma_send_byte(1); // active mode
- mma_stop();
-
- for (;;) {
- sys_tick_delay_ms(500);
-
- mma_start(0x4c, 1);
- mma_send_byte(0);
- mma_restart(0x4c, 0);
- for (int i = 0; i <= 3; i++) {
- int data;
- if (i == 3) {
- data = mma_read_nack();
- printf(" %02x\n", data);
- } else {
- data = mma_read_ack() & 0x3f;
- if (data & 0x20) {
- data |= 0xc0;
- }
- printf(" % 2d", data);
- }
- }
- }
- }
-
// SD card testing
if (0) {
//sdio_init();
diff --git a/stm/mma.c b/stm/mma.c
index 02f6d38c414e2b3960f48ac0d86dc573712f2bf6..48817b2d9786d1b978ed5fa82dc36976b505ca6f 100644
--- a/stm/mma.c
+++ b/stm/mma.c
@@ -4,22 +4,39 @@
#include <stm32f4xx_rcc.h>
#include <stm32f4xx_gpio.h>
+#include "misc.h"
+#include "systick.h"
#include "mma.h"
void mma_init(void) {
RCC->APB1ENR |= RCC_APB1ENR_I2C1EN; // enable I2C1
+
//gpio_pin_init(GPIOB, 6 /* B6 is SCL */, 2 /* AF mode */, 1 /* open drain output */, 1 /* 25 MHz */, 0 /* no pull up or pull down */);
//gpio_pin_init(GPIOB, 7 /* B7 is SDA */, 2 /* AF mode */, 1 /* open drain output */, 1 /* 25 MHz */, 0 /* no pull up or pull down */);
//gpio_pin_af(GPIOB, 6, 4 /* AF 4 for I2C1 */);
//gpio_pin_af(GPIOB, 7, 4 /* AF 4 for I2C1 */);
// XXX untested GPIO init! (was above code)
+
GPIO_InitTypeDef GPIO_InitStructure;
+
+ // PB5 is connected to AVDD; pull high to enable MMA device
+ GPIOB->BSRRH = GPIO_Pin_5; // PB5 low to start with
+ GPIO_InitStructure.GPIO_Pin = GPIO_Pin_5;
+ GPIO_InitStructure.GPIO_Mode = GPIO_Mode_OUT;
+ GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
+ GPIO_InitStructure.GPIO_Speed = GPIO_Speed_2MHz;
+ GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
+ GPIO_Init(GPIOB, &GPIO_InitStructure);
+
+ // PB6=SCL, PB7=SDA
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6 | GPIO_Pin_7;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
GPIO_InitStructure.GPIO_OType = GPIO_OType_OD;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_25MHz;
- GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL ;
+ GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
GPIO_Init(GPIOB, &GPIO_InitStructure);
+
+ // alternate functions for SCL and SDA
GPIO_PinAFConfig(GPIOB, GPIO_PinSource6, GPIO_AF_I2C1);
GPIO_PinAFConfig(GPIOB, GPIO_PinSource7, GPIO_AF_I2C1);
@@ -43,6 +60,11 @@ void mma_init(void) {
// enable the I2C peripheral
I2C1->CR1 |= I2C_CR1_PE;
+ // wait 20ms, then turn on AVDD, then wait 20ms again; this seems to work, but maybe can decrease delays
+ sys_tick_delay_ms(20);
+ GPIOB->BSRRL = GPIO_Pin_5;
+ sys_tick_delay_ms(20);
+
// set START bit in CR1 to generate a start cond!
}
@@ -58,27 +80,47 @@ void mma_restart(uint8_t addr, int write) {
I2C1->CR1 |= I2C_CR1_START;
// wait for BUSY, MSL and SB --> Slave has acknowledged start condition
+ uint32_t timeout = 1000000;
while ((i2c_get_sr() & 0x00030001) != 0x00030001) {
+ if (--timeout == 0) {
+ printf("timeout in mma_restart\n");
+ return;
+ }
}
if (write) {
// send address and write bit
I2C1->DR = (addr << 1) | 0;
// wait for BUSY, MSL, ADDR, TXE and TRA
+ timeout = 1000000;
while ((i2c_get_sr() & 0x00070082) != 0x00070082) {
+ if (--timeout == 0) {
+ printf("timeout in mma_restart write\n");
+ return;
+ }
}
} else {
// send address and read bit
I2C1->DR = (addr << 1) | 1;
// wait for BUSY, MSL and ADDR flags
+ timeout = 1000000;
while ((i2c_get_sr() & 0x00030002) != 0x00030002) {
+ if (--timeout == 0) {
+ printf("timeout in mma_restart read\n");
+ return;
+ }
}
}
}
void mma_start(uint8_t addr, int write) {
// wait until I2C is not busy
+ uint32_t timeout = 1000000;
while (I2C1->SR2 & I2C_SR2_BUSY) {
+ if (--timeout == 0) {
+ printf("timeout in mma_start\n");
+ return;
+ }
}
// do rest of start
@@ -89,11 +131,11 @@ void mma_send_byte(uint8_t data) {
// send byte
I2C1->DR = data;
// wait for TRA, BUSY, MSL, TXE and BTF (byte transmitted)
- int timeout = 1000000;
+ uint32_t timeout = 1000000;
while ((i2c_get_sr() & 0x00070084) != 0x00070084) {
- if (timeout-- <= 0) {
- printf("mma_send_byte timed out!\n");
- break;
+ if (--timeout == 0) {
+ printf("timeout in mma_send_byte\n");
+ return;
}
}
}
@@ -102,7 +144,12 @@ uint8_t mma_read_ack(void) {
// enable ACK of received byte
I2C1->CR1 |= I2C_CR1_ACK;
// wait for BUSY, MSL and RXNE (byte received)
+ uint32_t timeout = 1000000;
while ((i2c_get_sr() & 0x00030040) != 0x00030040) {
+ if (--timeout == 0) {
+ printf("timeout in mma_read_ack\n");
+ break;
+ }
}
// read and return data
uint8_t data = I2C1->DR;
@@ -115,7 +162,12 @@ uint8_t mma_read_nack(void) {
// last byte should apparently also generate a stop condition
I2C1->CR1 |= I2C_CR1_STOP;
// wait for BUSY, MSL and RXNE (byte received)
+ uint32_t timeout = 1000000;
while ((i2c_get_sr() & 0x00030040) != 0x00030040) {
+ if (--timeout == 0) {
+ printf("timeout in mma_read_nack\n");
+ break;
+ }
}
// read and return data
uint8_t data = I2C1->DR;