diff options
| author | Joel Challis <git@zvecr.com> | 2021-09-07 16:33:29 +0100 |
|---|---|---|
| committer | GitHub <noreply@github.com> | 2021-09-07 16:33:29 +0100 |
| commit | 2d6635214ab05858271f312619c5447bf317cf51 (patch) | |
| tree | 69cea964829f93c145aa60c734cd6d3b2e25a6ac /keyboards/ktec | |
| parent | 1dbe4e7dd0e0b1516997d84d16228e1d1ce29462 (diff) | |
| download | qmk_firmware-2d6635214ab05858271f312619c5447bf317cf51.tar.gz qmk_firmware-2d6635214ab05858271f312619c5447bf317cf51.zip | |
ergodone - Refactor use of legacy i2c implementation (#14340)
* Refactor use of legacy i2c implementation
* copy-paste error
Diffstat (limited to 'keyboards/ktec')
| -rw-r--r-- | keyboards/ktec/ergodone/expander.c | 28 | ||||
| -rw-r--r-- | keyboards/ktec/ergodone/i2cmaster.h | 178 | ||||
| -rw-r--r-- | keyboards/ktec/ergodone/rules.mk | 18 | ||||
| -rw-r--r-- | keyboards/ktec/ergodone/twimaster.c | 208 |
4 files changed, 15 insertions, 417 deletions
diff --git a/keyboards/ktec/ergodone/expander.c b/keyboards/ktec/ergodone/expander.c index 0c8a2289c..a4d48e9ed 100644 --- a/keyboards/ktec/ergodone/expander.c +++ b/keyboards/ktec/ergodone/expander.c | |||
| @@ -1,9 +1,11 @@ | |||
| 1 | #include <stdbool.h> | 1 | #include <stdbool.h> |
| 2 | #include "action.h" | 2 | #include "action.h" |
| 3 | #include "i2cmaster.h" | 3 | #include "i2c_master.h" |
| 4 | #include "expander.h" | 4 | #include "expander.h" |
| 5 | #include "debug.h" | 5 | #include "debug.h" |
| 6 | 6 | ||
| 7 | #define I2C_TIMEOUT 100 | ||
| 8 | |||
| 7 | static uint8_t expander_status = 0; | 9 | static uint8_t expander_status = 0; |
| 8 | static uint8_t expander_input = 0; | 10 | static uint8_t expander_input = 0; |
| 9 | 11 | ||
| @@ -20,7 +22,7 @@ void expander_init(void) | |||
| 20 | void expander_scan(void) | 22 | void expander_scan(void) |
| 21 | { | 23 | { |
| 22 | dprintf("expander status: %d ... ", expander_status); | 24 | dprintf("expander status: %d ... ", expander_status); |
| 23 | uint8_t ret = i2c_start(EXPANDER_ADDR | I2C_WRITE); | 25 | uint8_t ret = i2c_start(EXPANDER_ADDR | I2C_WRITE, I2C_TIMEOUT); |
| 24 | if (ret == 0) { | 26 | if (ret == 0) { |
| 25 | i2c_stop(); | 27 | i2c_stop(); |
| 26 | if (expander_status == 0) { | 28 | if (expander_status == 0) { |
| @@ -90,15 +92,7 @@ uint8_t expander_write(uint8_t reg, uint8_t data) | |||
| 90 | if (expander_status == 0) { | 92 | if (expander_status == 0) { |
| 91 | return 0; | 93 | return 0; |
| 92 | } | 94 | } |
| 93 | uint8_t ret; | 95 | return i2c_writeReg(EXPANDER_ADDR, reg, &data, 1, I2C_TIMEOUT); |
| 94 | ret = i2c_start(EXPANDER_ADDR | I2C_WRITE); | ||
| 95 | if (ret) goto stop; | ||
| 96 | ret = i2c_write(reg); | ||
| 97 | if (ret) goto stop; | ||
| 98 | ret = i2c_write(data); | ||
| 99 | stop: | ||
| 100 | i2c_stop(); | ||
| 101 | return ret; | ||
| 102 | } | 96 | } |
| 103 | 97 | ||
| 104 | uint8_t expander_read(uint8_t reg, uint8_t *data) | 98 | uint8_t expander_read(uint8_t reg, uint8_t *data) |
| @@ -106,15 +100,5 @@ uint8_t expander_read(uint8_t reg, uint8_t *data) | |||
| 106 | if (expander_status == 0) { | 100 | if (expander_status == 0) { |
| 107 | return 0; | 101 | return 0; |
| 108 | } | 102 | } |
| 109 | uint8_t ret; | 103 | return i2c_readReg(EXPANDER_ADDR, reg, data, 1, I2C_TIMEOUT); |
| 110 | ret = i2c_start(EXPANDER_ADDR | I2C_WRITE); | ||
| 111 | if (ret) goto stop; | ||
| 112 | ret = i2c_write(reg); | ||
| 113 | if (ret) goto stop; | ||
| 114 | ret = i2c_rep_start(EXPANDER_ADDR | I2C_READ); | ||
| 115 | if (ret) goto stop; | ||
| 116 | *data = i2c_readNak(); | ||
| 117 | stop: | ||
| 118 | i2c_stop(); | ||
| 119 | return ret; | ||
| 120 | } | 104 | } |
diff --git a/keyboards/ktec/ergodone/i2cmaster.h b/keyboards/ktec/ergodone/i2cmaster.h deleted file mode 100644 index 3917b9e6c..000000000 --- a/keyboards/ktec/ergodone/i2cmaster.h +++ /dev/null | |||
| @@ -1,178 +0,0 @@ | |||
| 1 | #ifndef _I2CMASTER_H | ||
| 2 | #define _I2CMASTER_H 1 | ||
| 3 | /************************************************************************* | ||
| 4 | * Title: C include file for the I2C master interface | ||
| 5 | * (i2cmaster.S or twimaster.c) | ||
| 6 | * Author: Peter Fleury <pfleury@gmx.ch> http://jump.to/fleury | ||
| 7 | * File: $Id: i2cmaster.h,v 1.10 2005/03/06 22:39:57 Peter Exp $ | ||
| 8 | * Software: AVR-GCC 3.4.3 / avr-libc 1.2.3 | ||
| 9 | * Target: any AVR device | ||
| 10 | * Usage: see Doxygen manual | ||
| 11 | **************************************************************************/ | ||
| 12 | |||
| 13 | #ifdef DOXYGEN | ||
| 14 | /** | ||
| 15 | @defgroup pfleury_ic2master I2C Master library | ||
| 16 | @code #include <i2cmaster.h> @endcode | ||
| 17 | |||
| 18 | @brief I2C (TWI) Master Software Library | ||
| 19 | |||
| 20 | Basic routines for communicating with I2C slave devices. This single master | ||
| 21 | implementation is limited to one bus master on the I2C bus. | ||
| 22 | |||
| 23 | This I2c library is implemented as a compact assembler software implementation of the I2C protocol | ||
| 24 | which runs on any AVR (i2cmaster.S) and as a TWI hardware interface for all AVR with built-in TWI hardware (twimaster.c). | ||
| 25 | Since the API for these two implementations is exactly the same, an application can be linked either against the | ||
| 26 | software I2C implementation or the hardware I2C implementation. | ||
| 27 | |||
| 28 | Use 4.7k pull-up resistor on the SDA and SCL pin. | ||
| 29 | |||
| 30 | Adapt the SCL and SDA port and pin definitions and eventually the delay routine in the module | ||
| 31 | i2cmaster.S to your target when using the software I2C implementation ! | ||
| 32 | |||
| 33 | Adjust the CPU clock frequence F_CPU in twimaster.c or in the Makfile when using the TWI hardware implementaion. | ||
| 34 | |||
| 35 | @note | ||
| 36 | The module i2cmaster.S is based on the Atmel Application Note AVR300, corrected and adapted | ||
| 37 | to GNU assembler and AVR-GCC C call interface. | ||
| 38 | Replaced the incorrect quarter period delays found in AVR300 with | ||
| 39 | half period delays. | ||
| 40 | |||
| 41 | @author Peter Fleury pfleury@gmx.ch http://jump.to/fleury | ||
| 42 | |||
| 43 | @par API Usage Example | ||
| 44 | The following code shows typical usage of this library, see example test_i2cmaster.c | ||
| 45 | |||
| 46 | @code | ||
| 47 | |||
| 48 | #include <i2cmaster.h> | ||
| 49 | |||
| 50 | |||
| 51 | #define Dev24C02 0xA2 // device address of EEPROM 24C02, see datasheet | ||
| 52 | |||
| 53 | int main(void) | ||
| 54 | { | ||
| 55 | unsigned char ret; | ||
| 56 | |||
| 57 | i2c_init(); // initialize I2C library | ||
| 58 | |||
| 59 | // write 0x75 to EEPROM address 5 (Byte Write) | ||
| 60 | i2c_start_wait(Dev24C02+I2C_WRITE); // set device address and write mode | ||
| 61 | i2c_write(0x05); // write address = 5 | ||
| 62 | i2c_write(0x75); // write value 0x75 to EEPROM | ||
| 63 | i2c_stop(); // set stop conditon = release bus | ||
| 64 | |||
| 65 | |||
| 66 | // read previously written value back from EEPROM address 5 | ||
| 67 | i2c_start_wait(Dev24C02+I2C_WRITE); // set device address and write mode | ||
| 68 | |||
| 69 | i2c_write(0x05); // write address = 5 | ||
| 70 | i2c_rep_start(Dev24C02+I2C_READ); // set device address and read mode | ||
| 71 | |||
| 72 | ret = i2c_readNak(); // read one byte from EEPROM | ||
| 73 | i2c_stop(); | ||
| 74 | |||
| 75 | for(;;); | ||
| 76 | } | ||
| 77 | @endcode | ||
| 78 | |||
| 79 | */ | ||
| 80 | #endif /* DOXYGEN */ | ||
| 81 | |||
| 82 | /**@{*/ | ||
| 83 | |||
| 84 | #if (__GNUC__ * 100 + __GNUC_MINOR__) < 304 | ||
| 85 | #error "This library requires AVR-GCC 3.4 or later, update to newer AVR-GCC compiler !" | ||
| 86 | #endif | ||
| 87 | |||
| 88 | #include <avr/io.h> | ||
| 89 | |||
| 90 | /** defines the data direction (reading from I2C device) in i2c_start(),i2c_rep_start() */ | ||
| 91 | #define I2C_READ 1 | ||
| 92 | |||
| 93 | /** defines the data direction (writing to I2C device) in i2c_start(),i2c_rep_start() */ | ||
| 94 | #define I2C_WRITE 0 | ||
| 95 | |||
| 96 | |||
| 97 | /** | ||
| 98 | @brief initialize the I2C master interace. Need to be called only once | ||
| 99 | @param void | ||
| 100 | @return none | ||
| 101 | */ | ||
| 102 | extern void i2c_init(void); | ||
| 103 | |||
| 104 | |||
| 105 | /** | ||
| 106 | @brief Terminates the data transfer and releases the I2C bus | ||
| 107 | @param void | ||
| 108 | @return none | ||
| 109 | */ | ||
| 110 | extern void i2c_stop(void); | ||
| 111 | |||
| 112 | |||
| 113 | /** | ||
| 114 | @brief Issues a start condition and sends address and transfer direction | ||
| 115 | |||
| 116 | @param addr address and transfer direction of I2C device | ||
| 117 | @retval 0 device accessible | ||
| 118 | @retval 1 failed to access device | ||
| 119 | */ | ||
| 120 | extern unsigned char i2c_start(unsigned char addr); | ||
| 121 | |||
| 122 | |||
| 123 | /** | ||
| 124 | @brief Issues a repeated start condition and sends address and transfer direction | ||
| 125 | |||
| 126 | @param addr address and transfer direction of I2C device | ||
| 127 | @retval 0 device accessible | ||
| 128 | @retval 1 failed to access device | ||
| 129 | */ | ||
| 130 | extern unsigned char i2c_rep_start(unsigned char addr); | ||
| 131 | |||
| 132 | |||
| 133 | /** | ||
| 134 | @brief Issues a start condition and sends address and transfer direction | ||
| 135 | |||
| 136 | If device is busy, use ack polling to wait until device ready | ||
| 137 | @param addr address and transfer direction of I2C device | ||
| 138 | @return none | ||
| 139 | */ | ||
| 140 | extern void i2c_start_wait(unsigned char addr); | ||
| 141 | |||
| 142 | |||
| 143 | /** | ||
| 144 | @brief Send one byte to I2C device | ||
| 145 | @param data byte to be transfered | ||
| 146 | @retval 0 write successful | ||
| 147 | @retval 1 write failed | ||
| 148 | */ | ||
| 149 | extern unsigned char i2c_write(unsigned char data); | ||
| 150 | |||
| 151 | |||
| 152 | /** | ||
| 153 | @brief read one byte from the I2C device, request more data from device | ||
| 154 | @return byte read from I2C device | ||
| 155 | */ | ||
| 156 | extern unsigned char i2c_readAck(void); | ||
| 157 | |||
| 158 | /** | ||
| 159 | @brief read one byte from the I2C device, read is followed by a stop condition | ||
| 160 | @return byte read from I2C device | ||
| 161 | */ | ||
| 162 | extern unsigned char i2c_readNak(void); | ||
| 163 | |||
| 164 | /** | ||
| 165 | @brief read one byte from the I2C device | ||
| 166 | |||
| 167 | Implemented as a macro, which calls either i2c_readAck or i2c_readNak | ||
| 168 | |||
| 169 | @param ack 1 send ack, request more data from device<br> | ||
| 170 | 0 send nak, read is followed by a stop condition | ||
| 171 | @return byte read from I2C device | ||
| 172 | */ | ||
| 173 | extern unsigned char i2c_read(unsigned char ack); | ||
| 174 | #define i2c_read(ack) (ack) ? i2c_readAck() : i2c_readNak(); | ||
| 175 | |||
| 176 | |||
| 177 | /**@}*/ | ||
| 178 | #endif | ||
diff --git a/keyboards/ktec/ergodone/rules.mk b/keyboards/ktec/ergodone/rules.mk index 7b88a1419..407afed03 100644 --- a/keyboards/ktec/ergodone/rules.mk +++ b/keyboards/ktec/ergodone/rules.mk | |||
| @@ -16,22 +16,22 @@ BOOTLOADER = caterina | |||
| 16 | # | 16 | # |
| 17 | CUSTOM_MATRIX = yes # Custom matrix file for the ErgoDone | 17 | CUSTOM_MATRIX = yes # Custom matrix file for the ErgoDone |
| 18 | UNICODE_ENABLE = yes # Unicode | 18 | UNICODE_ENABLE = yes # Unicode |
| 19 | BOOTMAGIC_ENABLE = lite # Enable Bootmagic Lite | 19 | BOOTMAGIC_ENABLE = yes # Enable Bootmagic Lite |
| 20 | MOUSEKEY_ENABLE = yes # Mouse keys | 20 | MOUSEKEY_ENABLE = yes # Mouse keys |
| 21 | EXTRAKEY_ENABLE = yes # Audio control and System control | 21 | EXTRAKEY_ENABLE = yes # Audio control and System control |
| 22 | CONSOLE_ENABLE = no # Console for debug | 22 | CONSOLE_ENABLE = no # Console for debug |
| 23 | COMMAND_ENABLE = no # Commands for debug and configuration | 23 | COMMAND_ENABLE = no # Commands for debug and configuration |
| 24 | SLEEP_LED_ENABLE = no # Breathing sleep LED during USB suspend | 24 | SLEEP_LED_ENABLE = no # Breathing sleep LED during USB suspend |
| 25 | NKRO_ENABLE = yes # USB Nkey Rollover - not yet supported in LUFA | 25 | NKRO_ENABLE = yes # USB Nkey Rollover - not yet supported in LUFA |
| 26 | USB_6KRO_ENABLE = no # USB 6key Rollover | 26 | USB_6KRO_ENABLE = no # USB 6key Rollover |
| 27 | BACKLIGHT_ENABLE = no # Enable keyboard backlight functionality | 27 | BACKLIGHT_ENABLE = no # Enable keyboard backlight functionality |
| 28 | SWAP_HANDS_ENABLE = no # Disable Onehand | 28 | SWAP_HANDS_ENABLE = no # Disable Onehand |
| 29 | RGBLIGHT_ENABLE = no | 29 | RGBLIGHT_ENABLE = no |
| 30 | 30 | ||
| 31 | # project specific files | 31 | # project specific files |
| 32 | QUANTUM_LIB_SRC += i2c_master.c | ||
| 32 | SRC = \ | 33 | SRC = \ |
| 33 | twimaster.c \ | 34 | matrix.c \ |
| 34 | matrix.c \ | 35 | expander.c \ |
| 35 | expander.c \ | ||
| 36 | 36 | ||
| 37 | LAYOUTS = ergodox | 37 | LAYOUTS = ergodox |
diff --git a/keyboards/ktec/ergodone/twimaster.c b/keyboards/ktec/ergodone/twimaster.c deleted file mode 100644 index d6f3f7840..000000000 --- a/keyboards/ktec/ergodone/twimaster.c +++ /dev/null | |||
| @@ -1,208 +0,0 @@ | |||
| 1 | /************************************************************************* | ||
| 2 | * Title: I2C master library using hardware TWI interface | ||
| 3 | * Author: Peter Fleury <pfleury@gmx.ch> http://jump.to/fleury | ||
| 4 | * File: $Id: twimaster.c,v 1.3 2005/07/02 11:14:21 Peter Exp $ | ||
| 5 | * Software: AVR-GCC 3.4.3 / avr-libc 1.2.3 | ||
| 6 | * Target: any AVR device with hardware TWI | ||
| 7 | * Usage: API compatible with I2C Software Library i2cmaster.h | ||
| 8 | **************************************************************************/ | ||
| 9 | #include <inttypes.h> | ||
| 10 | #include <compat/twi.h> | ||
| 11 | |||
| 12 | #include "i2cmaster.h" | ||
| 13 | |||
| 14 | |||
| 15 | /* define CPU frequency in Mhz here if not defined in Makefile */ | ||
| 16 | #ifndef F_CPU | ||
| 17 | #define F_CPU 16000000UL | ||
| 18 | #endif | ||
| 19 | |||
| 20 | /* I2C clock in Hz */ | ||
| 21 | #define SCL_CLOCK 400000L | ||
| 22 | |||
| 23 | |||
| 24 | /************************************************************************* | ||
| 25 | Initialization of the I2C bus interface. Need to be called only once | ||
| 26 | *************************************************************************/ | ||
| 27 | void i2c_init(void) | ||
| 28 | { | ||
| 29 | /* initialize TWI clock | ||
| 30 | * minimal values in Bit Rate Register (TWBR) and minimal Prescaler | ||
| 31 | * bits in the TWI Status Register should give us maximal possible | ||
| 32 | * I2C bus speed - about 444 kHz | ||
| 33 | * | ||
| 34 | * for more details, see 20.5.2 in ATmega16/32 secification | ||
| 35 | */ | ||
| 36 | |||
| 37 | TWSR = 0; /* no prescaler */ | ||
| 38 | TWBR = 10; /* must be >= 10 for stable operation */ | ||
| 39 | |||
| 40 | }/* i2c_init */ | ||
| 41 | |||
| 42 | |||
| 43 | /************************************************************************* | ||
| 44 | Issues a start condition and sends address and transfer direction. | ||
| 45 | return 0 = device accessible, 1= failed to access device | ||
| 46 | *************************************************************************/ | ||
| 47 | unsigned char i2c_start(unsigned char address) | ||
| 48 | { | ||
| 49 | uint8_t twst; | ||
| 50 | |||
| 51 | // send START condition | ||
| 52 | TWCR = (1<<TWINT) | (1<<TWSTA) | (1<<TWEN); | ||
| 53 | |||
| 54 | // wait until transmission completed | ||
| 55 | while(!(TWCR & (1<<TWINT))); | ||
| 56 | |||
| 57 | // check value of TWI Status Register. Mask prescaler bits. | ||
| 58 | twst = TW_STATUS & 0xF8; | ||
| 59 | if ( (twst != TW_START) && (twst != TW_REP_START)) return 1; | ||
| 60 | |||
| 61 | // send device address | ||
| 62 | TWDR = address; | ||
| 63 | TWCR = (1<<TWINT) | (1<<TWEN); | ||
| 64 | |||
| 65 | // wail until transmission completed and ACK/NACK has been received | ||
| 66 | while(!(TWCR & (1<<TWINT))); | ||
| 67 | |||
| 68 | // check value of TWI Status Register. Mask prescaler bits. | ||
| 69 | twst = TW_STATUS & 0xF8; | ||
| 70 | if ( (twst != TW_MT_SLA_ACK) && (twst != TW_MR_SLA_ACK) ) return 1; | ||
| 71 | |||
| 72 | return 0; | ||
| 73 | |||
| 74 | }/* i2c_start */ | ||
| 75 | |||
| 76 | |||
| 77 | /************************************************************************* | ||
| 78 | Issues a start condition and sends address and transfer direction. | ||
| 79 | If device is busy, use ack polling to wait until device is ready | ||
| 80 | |||
| 81 | Input: address and transfer direction of I2C device | ||
| 82 | *************************************************************************/ | ||
| 83 | void i2c_start_wait(unsigned char address) | ||
| 84 | { | ||
| 85 | uint8_t twst; | ||
| 86 | |||
| 87 | |||
| 88 | while ( 1 ) | ||
| 89 | { | ||
| 90 | // send START condition | ||
| 91 | TWCR = (1<<TWINT) | (1<<TWSTA) | (1<<TWEN); | ||
| 92 | |||
| 93 | // wait until transmission completed | ||
| 94 | while(!(TWCR & (1<<TWINT))); | ||
| 95 | |||
| 96 | // check value of TWI Status Register. Mask prescaler bits. | ||
| 97 | twst = TW_STATUS & 0xF8; | ||
| 98 | if ( (twst != TW_START) && (twst != TW_REP_START)) continue; | ||
| 99 | |||
| 100 | // send device address | ||
| 101 | TWDR = address; | ||
| 102 | TWCR = (1<<TWINT) | (1<<TWEN); | ||
| 103 | |||
| 104 | // wail until transmission completed | ||
| 105 | while(!(TWCR & (1<<TWINT))); | ||
| 106 | |||
| 107 | // check value of TWI Status Register. Mask prescaler bits. | ||
| 108 | twst = TW_STATUS & 0xF8; | ||
| 109 | if ( (twst == TW_MT_SLA_NACK )||(twst ==TW_MR_DATA_NACK) ) | ||
| 110 | { | ||
| 111 | /* device busy, send stop condition to terminate write operation */ | ||
| 112 | TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWSTO); | ||
| 113 | |||
| 114 | // wait until stop condition is executed and bus released | ||
| 115 | while(TWCR & (1<<TWSTO)); | ||
| 116 | |||
| 117 | continue; | ||
| 118 | } | ||
| 119 | //if( twst != TW_MT_SLA_ACK) return 1; | ||
| 120 | break; | ||
| 121 | } | ||
| 122 | |||
| 123 | }/* i2c_start_wait */ | ||
| 124 | |||
| 125 | |||
| 126 | /************************************************************************* | ||
| 127 | Issues a repeated start condition and sends address and transfer direction | ||
| 128 | |||
| 129 | Input: address and transfer direction of I2C device | ||
| 130 | |||
| 131 | Return: 0 device accessible | ||
| 132 | 1 failed to access device | ||
| 133 | *************************************************************************/ | ||
| 134 | unsigned char i2c_rep_start(unsigned char address) | ||
| 135 | { | ||
| 136 | return i2c_start( address ); | ||
| 137 | |||
| 138 | }/* i2c_rep_start */ | ||
| 139 | |||
| 140 | |||
| 141 | /************************************************************************* | ||
| 142 | Terminates the data transfer and releases the I2C bus | ||
| 143 | *************************************************************************/ | ||
| 144 | void i2c_stop(void) | ||
| 145 | { | ||
| 146 | /* send stop condition */ | ||
| 147 | TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWSTO); | ||
| 148 | |||
| 149 | // wait until stop condition is executed and bus released | ||
| 150 | while(TWCR & (1<<TWSTO)); | ||
| 151 | |||
| 152 | }/* i2c_stop */ | ||
| 153 | |||
| 154 | |||
| 155 | /************************************************************************* | ||
| 156 | Send one byte to I2C device | ||
| 157 | |||
| 158 | Input: byte to be transfered | ||
| 159 | Return: 0 write successful | ||
| 160 | 1 write failed | ||
| 161 | *************************************************************************/ | ||
| 162 | unsigned char i2c_write( unsigned char data ) | ||
| 163 | { | ||
| 164 | uint8_t twst; | ||
| 165 | |||
| 166 | // send data to the previously addressed device | ||
| 167 | TWDR = data; | ||
| 168 | TWCR = (1<<TWINT) | (1<<TWEN); | ||
| 169 | |||
| 170 | // wait until transmission completed | ||
| 171 | while(!(TWCR & (1<<TWINT))); | ||
| 172 | |||
| 173 | // check value of TWI Status Register. Mask prescaler bits | ||
| 174 | twst = TW_STATUS & 0xF8; | ||
| 175 | if( twst != TW_MT_DATA_ACK) return 1; | ||
| 176 | return 0; | ||
| 177 | |||
| 178 | }/* i2c_write */ | ||
| 179 | |||
| 180 | |||
| 181 | /************************************************************************* | ||
| 182 | Read one byte from the I2C device, request more data from device | ||
| 183 | |||
| 184 | Return: byte read from I2C device | ||
| 185 | *************************************************************************/ | ||
| 186 | unsigned char i2c_readAck(void) | ||
| 187 | { | ||
| 188 | TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWEA); | ||
| 189 | while(!(TWCR & (1<<TWINT))); | ||
| 190 | |||
| 191 | return TWDR; | ||
| 192 | |||
| 193 | }/* i2c_readAck */ | ||
| 194 | |||
| 195 | |||
| 196 | /************************************************************************* | ||
| 197 | Read one byte from the I2C device, read is followed by a stop condition | ||
| 198 | |||
| 199 | Return: byte read from I2C device | ||
| 200 | *************************************************************************/ | ||
| 201 | unsigned char i2c_readNak(void) | ||
| 202 | { | ||
| 203 | TWCR = (1<<TWINT) | (1<<TWEN); | ||
| 204 | while(!(TWCR & (1<<TWINT))); | ||
| 205 | |||
| 206 | return TWDR; | ||
| 207 | |||
| 208 | }/* i2c_readNak */ | ||
