| 0,0 → 1,252 |
|---|
| /*--------------------------------------------------------------------------*/ |
| /* RTC controls */ |
| |
| #include <avr/io.h> |
| #include <string.h> |
| #include "rtc.h" |
| |
| |
| |
| #define SCL_LOW() DDRE |= 0x04 /* SCL = LOW */ |
| #define SCL_HIGH() DDRE &= 0xFB /* SCL = High-Z */ |
| #define SCL_VAL ((PINE & 0x04) ? 1 : 0) /* SCL input level */ |
| #define SDA_LOW() DDRE |= 0x08 /* SDA = LOW */ |
| #define SDA_HIGH() DDRE &= 0xF7 /* SDA = High-Z */ |
| #define SDA_VAL ((PINE & 0x08) ? 1 : 0) /* SDA input level */ |
| |
| |
| |
| static |
| void iic_delay (void) |
| { |
| int n; |
| BYTE d; |
| |
| for (n = 4; n; n--) d = PINE; |
| } |
| |
| |
| /* Generate start condition on the IIC bus */ |
| static |
| void iic_start (void) |
| { |
| SDA_HIGH(); |
| iic_delay(); |
| SCL_HIGH(); |
| iic_delay(); |
| SDA_LOW(); |
| iic_delay(); |
| SCL_LOW(); |
| iic_delay(); |
| } |
| |
| |
| /* Generate stop condition on the IIC bus */ |
| static |
| void iic_stop (void) |
| { |
| SDA_LOW(); |
| iic_delay(); |
| SCL_HIGH(); |
| iic_delay(); |
| SDA_HIGH(); |
| iic_delay(); |
| } |
| |
| |
| /* Send a byte to the IIC bus */ |
| static |
| BOOL iic_send (BYTE dat) |
| { |
| BYTE b = 0x80; |
| BOOL ack; |
| |
| |
| do { |
| if (dat & b) { /* SDA = Z/L */ |
| SDA_HIGH(); |
| } else { |
| SDA_LOW(); |
| } |
| iic_delay(); |
| SCL_HIGH(); |
| iic_delay(); |
| SCL_LOW(); |
| iic_delay(); |
| } while (b >>= 1); |
| SDA_HIGH(); |
| iic_delay(); |
| SCL_HIGH(); |
| ack = SDA_VAL ? FALSE : TRUE; /* Sample ACK */ |
| iic_delay(); |
| SCL_LOW(); |
| iic_delay(); |
| return ack; |
| } |
| |
| |
| /* Receive a byte from the IIC bus */ |
| static |
| BYTE iic_rcvr (BOOL ack) |
| { |
| UINT d = 1; |
| |
| |
| do { |
| d <<= 1; |
| SCL_HIGH(); |
| if (SDA_VAL) d++; |
| iic_delay(); |
| SCL_LOW(); |
| iic_delay(); |
| } while (d < 0x100); |
| if (ack) { /* SDA = ACK */ |
| SDA_LOW(); |
| } else { |
| SDA_HIGH(); |
| } |
| iic_delay(); |
| SCL_HIGH(); |
| iic_delay(); |
| SCL_LOW(); |
| SDA_HIGH(); |
| iic_delay(); |
| |
| return (BYTE)d; |
| } |
| |
| |
| |
| |
| BOOL rtc_read ( |
| UINT adr, /* Read start address */ |
| UINT cnt, /* Read byte count */ |
| void* buff /* Read data buffer */ |
| ) |
| { |
| BYTE *rbuff = buff; |
| int n; |
| |
| |
| if (!cnt) return FALSE; |
| |
| n = 10; |
| do { /* Select DS1338 (0xD0) */ |
| iic_start(); |
| } while (!iic_send(0xD0) && --n); |
| if (!n) return FALSE; |
| |
| if (iic_send((BYTE)adr)) { /* Set start address */ |
| iic_start(); /* Reselect DS1338 in read mode (0xD1) */ |
| if (iic_send(0xD1)) { |
| do { /* Receive data */ |
| cnt--; |
| *rbuff++ = iic_rcvr(cnt ? TRUE : FALSE); |
| } while (cnt); |
| } |
| } |
| |
| iic_stop(); /* Deselect device */ |
| |
| return cnt ? FALSE : TRUE; |
| } |
| |
| |
| |
| |
| BOOL rtc_write ( |
| UINT adr, /* Write start address */ |
| UINT cnt, /* Write byte count */ |
| const void* buff /* Data to be written */ |
| ) |
| { |
| const BYTE *wbuff = buff; |
| int n; |
| |
| |
| if (!cnt) return FALSE; |
| |
| n = 10; |
| do { /* Select DS1338 (0xD0) */ |
| iic_start(); |
| } while (!iic_send(0xD0) && --n); |
| if (!n) return FALSE; |
| |
| if (iic_send((BYTE)adr)) { /* Set start address */ |
| do { /* Send data */ |
| if (!iic_send(*wbuff++)) break; |
| } while (--cnt); |
| } |
| |
| iic_stop(); /* Deselect device */ |
| |
| return cnt ? FALSE : TRUE; |
| } |
| |
| |
| |
| |
| BOOL rtc_gettime (RTC *rtc) |
| { |
| BYTE buf[8]; |
| |
| |
| if (!rtc_read(0, 7, buf)) return FALSE; |
| |
| rtc->sec = (buf[0] & 0x0F) + ((buf[0] >> 4) & 7) * 10; |
| rtc->min = (buf[1] & 0x0F) + (buf[1] >> 4) * 10; |
| rtc->hour = (buf[2] & 0x0F) + ((buf[2] >> 4) & 3) * 10; |
| rtc->mday = (buf[4] & 0x0F) + ((buf[4] >> 4) & 3) * 10; |
| rtc->month = (buf[5] & 0x0F) + ((buf[5] >> 4) & 1) * 10; |
| rtc->year = 2000 + (buf[6] & 0x0F) + (buf[6] >> 4) * 10; |
| |
| return TRUE; |
| } |
| |
| |
| |
| |
| BOOL rtc_settime (const RTC *rtc) |
| { |
| |
| BYTE buf[8]; |
| |
| |
| buf[0] = rtc->sec / 10 * 16 + rtc->sec % 10; |
| buf[1] = rtc->min / 10 * 16 + rtc->min % 10; |
| buf[2] = rtc->hour / 10 * 16 + rtc->hour % 10; |
| buf[3] = 0; |
| buf[4] = rtc->mday / 10 * 16 + rtc->mday % 10; |
| buf[5] = rtc->month / 10 * 16 + rtc->month % 10; |
| buf[6] = (rtc->year - 2000) / 10 * 16 + (rtc->year - 2000) % 10; |
| rtc_write(0, 7, buf); |
| |
| return TRUE; |
| } |
| |
| |
| |
| |
| BOOL rtc_init (void) |
| { |
| BYTE buf[8]; /* RTC R/W buffer */ |
| UINT n; |
| |
| |
| /* Read RTC registers */ |
| if (!rtc_read(0, 8, buf)) return FALSE; /* IIC error */ |
| |
| if (buf[7] & 0x20) { /* When RTC data has been broken, set default time */ |
| /* Reset time to Jan 1, '08 */ |
| memset(buf, 0, 8); |
| buf[4] = 1; buf[5] = 1; buf[6] = 8; |
| rtc_write(0, 8, buf); |
| /* Clear data memory */ |
| memset(buf, 0, 8); |
| for (n = 8; n < 64; n += 8) |
| rtc_write(n, 8, buf); |
| return FALSE; |
| } |
| return TRUE; |
| } |
| |