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-rw-r--r--main.c327
1 files changed, 6 insertions, 321 deletions
diff --git a/main.c b/main.c
index 62e10d3..6bda270 100644
--- a/main.c
+++ b/main.c
@@ -5,135 +5,13 @@
#include <avr/interrupt.h>
#include <avr/sleep.h>
#include <util/delay.h>
-#include <util/twi.h>
#include <stdio.h>
#include <stdbool.h>
-/* i2c device addresses */
-#define L3GD20 0b11010100
-#define L3GD20_WHOAMI 0xf
-#define L3GD20_CTRLREG1 0x20
-#define LIS302DL 0b00111000
-#define LIS302DL_WHOAMI 0xf
-#define LIS302DL_CTRLREG1 0x20
+#include "i2c.h"
+#include "uart.h"
-typedef enum {
- TWM_INVALID = 0,
- TWM_WRITE,
- TWM_READ_MULTI,
-} twMode;
-
-typedef enum {
- TWST_WAIT = 0,
- TWST_OK = 1,
- TWST_ERR = 2,
-} twStatus;
-
-typedef struct {
- twMode mode;
- uint8_t address;
- uint8_t subaddress;
- uint8_t data;
- uint8_t step;
- /* read data store */
- uint8_t *retData;
- /* number of bytes to be read */
- uint8_t count;
- /* current byte */
- uint8_t i;
- twStatus status;
-} twReq;
-
-volatile twReq twr;
-
-void twStartRaw () {
- /* disable stop, enable interrupt, reset twint, enable start, enable i2c */
- TWCR = (TWCR & ~(1 << TWSTO)) | (1 << TWIE) | (1 << TWINT) | (1 << TWSTA) | (1 << TWEN);
-}
-
-void twStopRaw () {
- /* disable start, enable interrupt, reset twint, enable stop, enable i2c */
- TWCR = (TWCR & ~(1 << TWSTA)) | (1 << TWIE) | (1 << TWINT) | (1 << TWSTO) | (1 << TWEN);
-}
-
-void twFlushRaw () {
- /* disable start/stop, enable interrupt, reset twint, enable i2c */
- TWCR = (TWCR & ~((1 << TWSTA) | (1 << TWSTO) | (1 << TWEA))) | (1 << TWIE) | (1 << TWINT) | (1 << TWEN);
-}
-
-/* flush and send master ack */
-void twFlushContRaw () {
- /* disable start/stop, enable interrupt, reset twint, enable i2c, send master ack */
- TWCR = (TWCR & ~((1 << TWSTA) | (1 << TWSTO))) | (1 << TWIE) | (1 << TWINT) | (1 << TWEN) | (1 << TWEA);
-}
-
-void twWaitRaw () {
- while (!(TWCR & (1 << TWINT)));
-}
-
-bool twWriteRaw (uint8_t data) {
- TWDR = data;
- if (TWCR & (1 << TWWC)) {
- printf("write collision\n");
- return false;
- } else {
- return true;
- }
-}
-
-void twInit () {
- /* set scl to 3.6 kHz (at 1Mhz CPU speed)*/
- TWBR = 2;
- TWSR |= 0x3; /* set prescaler to 64 */
-
- twr.mode = TWM_INVALID;
- twr.status = TWST_ERR;
-}
-
-/* high-level write
- */
-static bool twWrite (uint8_t address, uint8_t subaddress, uint8_t data) {
- /* do not start if request is pending */
- if (twr.status == TWST_WAIT) {
- return false;
- }
-
- twr.mode = TWM_WRITE;
- twr.address = address;
- twr.subaddress = subaddress;
- twr.data = data;
- twr.step = 0;
- twr.status = TWST_WAIT;
- /* wait for stop finish */
- while (TW_STATUS != 0xf8);
- twStartRaw ();
-
- return true;
-}
-
-static bool twReadMulti (uint8_t address, uint8_t subaddress,
- uint8_t *retData, uint8_t count) {
- /* do not start if request is pending */
- if (twr.status == TWST_WAIT) {
- return false;
- }
-
- twr.mode = TWM_READ_MULTI;
- twr.address = address;
- twr.subaddress = subaddress;
- twr.retData = retData;
- twr.count = count;
- twr.i = 0;
- twr.step = 0;
- twr.status = TWST_WAIT;
- /* wait for stop finish */
- while (TW_STATUS != 0xf8);
- twStartRaw ();
-
- return true;
-}
-
-void ledInit () {
+static void ledInit () {
/* set led1,led2 to output */
DDRB |= (1 << PB6) | (1 << PB7);
/* set led3,led4,led5,led6 to output */
@@ -141,208 +19,18 @@ void ledInit () {
}
/* show data with leds */
-void ledShow (unsigned char val) {
+static void ledShow (const unsigned char val) {
PORTB = (PORTB & ~((1 << PB6) | (1 << PB7))) | ((val & 0x3) << PB6);
PORTD = (PORTD & ~((1 << PD2) | (1 << PD3) | (1 << PD4) | (1 << PD5))) | (((val >> 2) & 0xf) << PD2);
}
-void uartInit () {
- /* Set baud rate (9600, double speed, at 1mhz) */
- UBRR0H = 0;
- UBRR0L = 12;
- /* enable double speed mode */
- UCSR0A = (1 << U2X0);
- /* Enable receiver and transmitter */
- UCSR0B = (1<<RXEN0)|(1<<TXEN0);
- /* Set frame format: 8 data, 1 stop bit, even parity */
- UCSR0C = (1<<UPM01) | (0 << UPM00) | (0<<USBS0)|(3<<UCSZ00);
-}
-
-/* blocking uart send
- */
-void uartSend (unsigned char data) {
- /* Wait for empty transmit buffer */
- while (!( UCSR0A & (1<<UDRE0)));
- /* Put data into buffer, sends the data */
- UDR0 = data;
-}
-
-int uartPutc (char c, FILE *stream) {
- if (c == '\n') {
- uartSend ('\r');
- }
- uartSend (c);
- return 0;
-}
-
-static FILE mystdout = FDEV_SETUP_STREAM (uartPutc, NULL, _FDEV_SETUP_WRITE);
-
-unsigned char uartReceive () {
- /* Wait for data to be received */
- while ( !(UCSR0A & (1<<RXC0)) );
- /* Get and return received data from buffer */
- return UDR0;
-}
-
-void cpuInit () {
+static void cpuInit () {
/* enter change prescaler mode */
CLKPR = CLKPCE << 1;
/* write new prescaler = 8 (i.e. 1Mhz clock frequency) */
CLKPR = 0b00000011;
}
-/* handle interrupt, write request
- */
-static void twIntWrite () {
- switch (twr.step) {
- case 0:
- if (TW_STATUS == TW_START) {
- twWriteRaw (twr.address | TW_WRITE);
- twFlushRaw ();
- } else {
- twr.status = TWST_ERR;
- }
- break;
-
- case 1:
- if (TW_STATUS == TW_MT_SLA_ACK) {
- twWriteRaw (twr.subaddress);
- twFlushRaw ();
- } else {
- twr.status = TWST_ERR;
- }
- break;
-
- case 2:
- if (TW_STATUS == TW_MT_DATA_ACK) {
- twWriteRaw (twr.data);
- twFlushRaw ();
- } else {
- twr.status = TWST_ERR;
- }
- break;
-
- case 3:
- if (TW_STATUS == TW_MT_DATA_ACK) {
- twStopRaw ();
- twr.status = TWST_OK;
- } else {
- twr.status = TWST_ERR;
- }
- break;
-
- default:
- printf ("nope\n");
- break;
- }
- ++twr.step;
-}
-
-static void twIntReadMulti () {
- switch (twr.step) {
- case 0:
- if (TW_STATUS == TW_START) {
- /* write device address */
- twWriteRaw (twr.address | TW_WRITE);
- twFlushRaw ();
- ++twr.step;
- } else {
- twr.status = TWST_ERR;
- }
- break;
-
- case 1:
- if (TW_STATUS == TW_MT_SLA_ACK) {
- /* write subaddress, enable auto-increment */
- twWriteRaw ((1 << 7) | twr.subaddress);
- twFlushRaw ();
- ++twr.step;
- } else {
- twr.status = TWST_ERR;
- }
- break;
-
- case 2:
- if (TW_STATUS == TW_MT_DATA_ACK) {
- /* send repeated start */
- twStartRaw ();
- ++twr.step;
- } else {
- twr.status = TWST_ERR;
- }
- break;
-
- case 3:
- if (TW_STATUS == TW_REP_START) {
- /* now start the actual read request */
- twWriteRaw (twr.address | TW_READ);
- twFlushRaw ();
- ++twr.step;
- } else {
- twr.status = TWST_ERR;
- }
- break;
-
- case 4:
- if (TW_STATUS == TW_MR_SLA_ACK) {
- /* send master ack if next data block is received */
- twFlushContRaw ();
- ++twr.step;
- } else {
- twr.status = TWST_ERR;
- }
-
- case 5:
- if (TW_STATUS == TW_MR_DATA_ACK) {
- twr.retData[twr.i] = TWDR;
- ++twr.i;
- if (twr.i < twr.count-1) {
- /* read another byte, not the last one */
- twFlushContRaw ();
- /* step stays the same */
- } else {
- /* read last byte, send master nack */
- twFlushRaw ();
- ++twr.step;
- }
- } else {
- twr.status = TWST_ERR;
- }
- break;
-
- case 6:
- if (TW_STATUS == TW_MR_DATA_NACK) {
- /* receive final byte, send stop */
- twr.retData[twr.i] = TWDR;
- twStopRaw ();
- twr.status = TWST_OK;
- } else {
- twr.status = TWST_ERR;
- }
- break;
-
- default:
- printf ("twIntReadMulti: nope\n");
- break;
- }
-}
-
-ISR(TWI_vect) {
- switch (twr.mode) {
- case TWM_WRITE:
- twIntWrite ();
- break;
-
- case TWM_READ_MULTI:
- twIntReadMulti ();
- break;
-
- default:
- printf ("nope\n");
- break;
- }
-}
-
volatile unsigned char count;
ISR(TIMER0_OVF_vect) {
@@ -355,16 +43,13 @@ ISR(TIMER0_OVF_vect) {
while (cond) { sleep_cpu (); } \
sleep_disable ();
-int main(void) {
+int main () {
cpuInit ();
ledInit ();
twInit ();
uartInit ();
set_sleep_mode (SLEEP_MODE_IDLE);
- /* redirect stdout */
- stdout = &mystdout;
-
printf ("initialization done\n");
/* global interrupt enable */
generated by cgit v1.2.3 (git 2.39.1) at 2024-04-18 22:25:12 +0000