diff options
Diffstat (limited to 'firmware/i2c.c')
| -rw-r--r-- | firmware/i2c.c | 216 |
1 files changed, 216 insertions, 0 deletions
diff --git a/firmware/i2c.c b/firmware/i2c.c new file mode 100644 index 0000000..b7d55fe --- /dev/null +++ b/firmware/i2c.c @@ -0,0 +1,216 @@ +/* + * Author: Benedikt Sauter + * Author: Peter Huewe, Hubert Hogel + * All rights reserved. + * + * Short descripton of file: + * + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials provided + * with the distribution. + * * Neither the name of the FH Augsburg nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#include "common.h" +#include "protocol.h" +#include "i2c.h" + +void i2c_parser(char *buf) { +answer[0] = buf[0]; + switch(buf[0]){ + case CMD_I2C_INIT: + i2c_init_usb(); + break; + case CMD_I2C_DEINIT: + i2c_deinit_usb(); + break; + case CMD_I2C_SET_BITRATE: + i2c_set_bitrate_usb((char)buf[2]); + break; + case CMD_I2C_SEND_BYTE: + i2c_send_byte_usb((int)buf[2]); + break; + case CMD_I2C_RECV_BYTES: + i2c_reveice_bytes_usb((int)buf[3],(int)buf[1]-4, (int)buf[2]); + break; + case CMD_I2C_SEND_START: + i2c_send_start_usb(); + break; + case CMD_I2C_SEND_STOP: + i2c_send_stop_usb(); + break; + default: + answer[0]=buf[0]; + answer[1]=RSP_UNKOWN_CMD; + answer[2]=0; + CommandAnswer(3); + } +} + + +unsigned char i2c_get_twsr(void) +{ + return (TWSR & 0xF8); +} + + +void i2c_wait_for_complete(void) +{ + while (!(TWCR & (1<<TWINT))){ + //do nothing just wait + ; + } +} + + +void i2c_init_usb(void) +{ + answer[0]=CMD_I2C_INIT; + answer[1]=(unsigned char)i2c_init(); + answer[2]=0; + CommandAnswer(3); +} + +int i2c_init(void) +{ + TWCR |= (1<<TWEN); + octopus.ports[12] = PIN_SCL; + octopus.ports[13] = PIN_SDA; + + return RSP_OK; +} + + +void i2c_deinit_usb(void) +{ + answer[0]=CMD_I2C_DEINIT; + answer[1]=(unsigned char)i2c_deinit(); + answer[2]=0; + CommandAnswer(3); +} + +int i2c_deinit(void) +{ + TWCR &= ~(1<<TWEN); // deinit + octopus.ports[12]=PIN_OUT; // this is wrong! + octopus.ports[13]=PIN_OUT; // this is wrong! + + return RSP_OK; +} + + +void i2c_set_bitrate_usb(char bitrate) { + answer[0] = CMD_I2C_SET_BITRATE; + answer[1] = (unsigned char)i2c_set_bitrate(bitrate); + answer[2] = '\0'; + CommandAnswer(3); +} + +int i2c_set_bitrate(char bitrate) { + TWBR = bitrate; + + TWSR &= ~((1<<TWPS1) | (1<<TWPS0)); + TWSR |= (0<<TWPS0); + + return RSP_OK; +} + + +void i2c_send_start_usb(void) +{ + answer[0] = CMD_I2C_SEND_START; + answer[1] = (unsigned char)i2c_send_start(); + answer[2] = '\0'; + CommandAnswer(3); +} + +int i2c_send_start(void) +{ + i2c_get_twsr(); + TWCR = (1<<TWINT) | (1<<TWSTA) | (1<<TWEN); + i2c_wait_for_complete(); + return RSP_OK; +} + +void i2c_send_stop_usb(void) +{ + answer[0]=CMD_I2C_SEND_STOP; + answer[1]=(unsigned char)i2c_send_stop(); + answer[2]=0; + CommandAnswer(3); +} + + +int i2c_send_stop(void) +{ + TWCR = (1<<TWINT)|(1<<TWEN)|(1<<TWSTO); + return RSP_OK; +} + + +void i2c_send_byte_usb(char data) +{ + i2c_send_byte(data); + + answer[0] = CMD_I2C_SEND_BYTE; + answer[1] = RSP_OK; + answer[2] = '\0'; + CommandAnswer(3); +} + +void i2c_send_byte(char data) +{ + TWDR = data; + TWCR = (1<<TWINT) | (1<<TWEN); + i2c_wait_for_complete(); +} + +void i2c_reveice_bytes_usb(int address,int len, int timeout) +{ + /* receive */ + //i2c_get_twsr(); + //print_hex(s); + + //i2c_send_start(); + /* slave address = 0x10; */ + //buf[3] = (0x10 << 1)|1; /* (00010000<<1) | R */ + //i2c_send_byte( (0x10 << 1)|1); + + + answer[0]=CMD_I2C_RECV_BYTES; + answer[1]=RSP_OK; + answer[2]=1; + answer[3]=i2c_receive_byte(); + CommandAnswer(5); +} + + +unsigned char i2c_receive_byte(void) +{ + TWCR = (1<<TWINT) | (1<<TWEN); + i2c_wait_for_complete(); + return TWDR; +} + |