diff options
Diffstat (limited to 'Firmware/swi2c.cpp')
| -rw-r--r-- | Firmware/swi2c.cpp | 209 |
1 files changed, 209 insertions, 0 deletions
diff --git a/Firmware/swi2c.cpp b/Firmware/swi2c.cpp new file mode 100644 index 000000000..272ac4192 --- /dev/null +++ b/Firmware/swi2c.cpp @@ -0,0 +1,209 @@ +#include "uni_avr_rpi.h" + +#ifdef SWI2C +#include "swi2c.h" + +#ifdef __AVR +unsigned char swi2c_sda = 20; // SDA pin +unsigned char swi2c_scl = 21; // SCL pin +#endif //__AVR + +#ifdef __RPI +unsigned char swi2c_sda = 2; // SDA pin +unsigned char swi2c_scl = 3; // SCL pin +#endif //__RPI + +unsigned char swi2c_cfg = 0xb1; // config +// bit0..3 = clock delay factor = 1 << 1 = 2 [us] +// bit4..7 = ack timeout factor = 1 << 11 = 2048 [cycles] + +#define SWI2C_SDA swi2c_sda +#define SWI2C_SCL swi2c_scl +#define SWI2C_RMSK 0x01 //read mask (bit0 = 1) +#define SWI2C_WMSK 0x00 //write mask (bit0 = 0) +#define SWI2C_ASHF 0x01 //address shift (<< 1) +#define SWI2C_DMSK 0x7f //device address mask + + +void swi2c_init(unsigned char sda, unsigned char scl, unsigned char cfg) +{ + swi2c_sda = sda; + swi2c_scl = scl; + swi2c_cfg = cfg; + GPIO_OUT(SWI2C_SDA); + GPIO_OUT(SWI2C_SCL); + GPIO_SET(SWI2C_SDA); + GPIO_SET(SWI2C_SCL); + DELAY(1000); +} + +void swi2c_start(int delay) +{ + GPIO_CLR(SWI2C_SDA); + DELAY(delay); + GPIO_CLR(SWI2C_SCL); + DELAY(delay); +} + +void swi2c_stop(int delay) +{ + GPIO_SET(SWI2C_SCL); + DELAY(delay); + GPIO_SET(SWI2C_SDA); + DELAY(delay); +} + +void swi2c_ack(int delay) +{ + GPIO_CLR(SWI2C_SDA); + DELAY(delay); + GPIO_SET(SWI2C_SCL); + DELAY(delay); + GPIO_CLR(SWI2C_SCL); + DELAY(delay); +} + +int swi2c_wait_ack(int delay, int ackto) +{ + GPIO_INP(SWI2C_SDA); + DELAY(delay); +// GPIO_SET(SWI2C_SDA); + DELAY(delay); + GPIO_SET(SWI2C_SCL); +// DELAY(delay); + int ack = 0; + while (!(ack = !GPIO_GET(SWI2C_SDA)) && ackto--) DELAY(delay); + GPIO_CLR(SWI2C_SCL); + DELAY(delay); + GPIO_OUT(SWI2C_SDA); + DELAY(delay); + GPIO_CLR(SWI2C_SDA); + DELAY(delay); + return ack; +} + +unsigned char swi2c_read(int delay) +{ + GPIO_SET(SWI2C_SDA); + DELAY(delay); + GPIO_INP(SWI2C_SDA); + unsigned char data = 0; + int bit; for (bit = 7; bit >= 0; bit--) + { + GPIO_SET(SWI2C_SCL); + DELAY(delay); + data |= GPIO_GET(SWI2C_SDA) << bit; + GPIO_CLR(SWI2C_SCL); + DELAY(delay); + } + GPIO_OUT(SWI2C_SDA); + return data; +} + +void swi2c_write(int delay, unsigned char data) +{ + int bit; for (bit = 7; bit >= 0; bit--) + { + if (data & (1 << bit)) GPIO_SET(SWI2C_SDA); + else GPIO_CLR(SWI2C_SDA); + DELAY(delay); + GPIO_SET(SWI2C_SCL); + DELAY(delay); + GPIO_CLR(SWI2C_SCL); + DELAY(delay); + } +} + +int swi2c_check(unsigned char dev_addr) +{ + int delay = 1 << (swi2c_cfg & 0xf); + int tmout = 1 << (swi2c_cfg >> 4); + swi2c_start(delay); + swi2c_write(delay, (dev_addr & SWI2C_DMSK) << SWI2C_ASHF); + if (!swi2c_wait_ack(delay, tmout)) { swi2c_stop(delay); return 0; } + swi2c_stop(delay); + return 1; +} + +#ifdef SWI2C_A8 //8bit address + +int swi2c_readByte_A8(unsigned char dev_addr, unsigned char addr, unsigned char* pbyte) +{ + int delay = 1 << (swi2c_cfg & 0xf); + int tmout = 1 << (swi2c_cfg >> 4); + swi2c_start(delay); + swi2c_write(delay, SWI2C_WMSK | ((dev_addr & SWI2C_DMSK) << SWI2C_ASHF)); + if (!swi2c_wait_ack(delay, tmout)) { swi2c_stop(delay); return 0; } + swi2c_write(delay, addr & 0xff); + if (!swi2c_wait_ack(delay, tmout)) return 0; + swi2c_stop(delay); + swi2c_start(delay); + swi2c_write(delay, SWI2C_RMSK | ((dev_addr & SWI2C_DMSK) << SWI2C_ASHF)); + if (!swi2c_wait_ack(delay, tmout)) return 0; + unsigned char byte = swi2c_read(delay); + swi2c_stop(delay); + if (pbyte) *pbyte = byte; + return 1; +} + +int swi2c_writeByte_A8(unsigned char dev_addr, unsigned char addr, unsigned char* pbyte) +{ + int delay = 1 << (swi2c_cfg & 0xf); + int tmout = 1 << (swi2c_cfg >> 4); + swi2c_start(delay); + swi2c_write(delay, SWI2C_WMSK | ((dev_addr & SWI2C_DMSK) << SWI2C_ASHF)); + if (!swi2c_wait_ack(delay, tmout)) { swi2c_stop(delay); return 0; } + swi2c_write(delay, addr & 0xff); + if (!swi2c_wait_ack(delay, tmout)) return 0; + swi2c_write(delay, *pbyte); + if (!swi2c_wait_ack(delay, tmout)) return 0; + swi2c_stop(delay); + return 1; +} + +#endif //SWI2C_A8 + +#ifdef SWI2C_A16 //16bit address + +int swi2c_readByte_A16(unsigned char dev_addr, unsigned short addr, unsigned char* pbyte) +{ + int delay = 1 << (swi2c_cfg & 0xf); + int tmout = 1 << (swi2c_cfg >> 4); + swi2c_start(delay); + swi2c_write(delay, SWI2C_WMSK | ((dev_addr & SWI2C_DMSK) << SWI2C_ASHF)); + if (!swi2c_wait_ack(delay, tmout)) { swi2c_stop(delay); return 0; } + swi2c_write(delay, addr >> 8); + if (!swi2c_wait_ack(delay, tmout)) return 0; + swi2c_write(delay, addr & 0xff); + if (!swi2c_wait_ack(delay, tmout)) return 0; + swi2c_stop(delay); + swi2c_start(delay); + swi2c_write(delay, SWI2C_RMSK | ((dev_addr & SWI2C_DMSK) << SWI2C_ASHF)); + if (!swi2c_wait_ack(delay, tmout)) return 0; + unsigned char byte = swi2c_read(delay); + swi2c_stop(delay); + if (pbyte) *pbyte = byte; + return 1; +} + +int swi2c_writeByte_A16(unsigned char dev_addr, unsigned short addr, unsigned char* pbyte) +{ + int delay = 1 << (swi2c_cfg & 0xf); + int tmout = 1 << (swi2c_cfg >> 4); + swi2c_start(delay); + swi2c_write(delay, SWI2C_WMSK | ((dev_addr & SWI2C_DMSK) << SWI2C_ASHF)); + if (!swi2c_wait_ack(delay, tmout)) { swi2c_stop(delay); return 0; } + swi2c_write(delay, addr >> 8); + if (!swi2c_wait_ack(delay, tmout)) return 0; + swi2c_write(delay, addr & 0xff); + if (!swi2c_wait_ack(delay, tmout)) return 0; + swi2c_write(delay, *pbyte); + if (!swi2c_wait_ack(delay, tmout)) return 0; + swi2c_stop(delay); + return 1; +} + +#endif //SWI2C_A16 + + +#endif //SWI2C
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