diff options
Diffstat (limited to 'i2c.c')
| -rw-r--r-- | i2c.c | 52 |
1 files changed, 18 insertions, 34 deletions
@@ -52,39 +52,17 @@ void twInit () { /* high-level write */ -bool twWrite (const uint8_t address, const uint8_t subaddress, - const uint8_t data) { +bool twRequest (const twMode mode, const uint8_t address, + const uint8_t subaddress, uint8_t * const data, const uint8_t count) { /* do not start if request is pending */ if (twr.status == TWST_WAIT) { return false; } - twr.mode = TWM_WRITE; + twr.mode = mode; 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; -} - -/* high-level read for multiple bytes/addresses - */ -bool twReadMulti (const uint8_t address, const uint8_t subaddress, - uint8_t * const retData, const 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; @@ -104,6 +82,7 @@ static void twIntWrite () { if (TW_STATUS == TW_START) { twWriteRaw (twr.address | TW_WRITE); twFlushRaw (); + ++twr.step; } else { twr.status = TWST_ERR; } @@ -111,8 +90,10 @@ static void twIntWrite () { case 1: if (TW_STATUS == TW_MT_SLA_ACK) { - twWriteRaw (twr.subaddress); + /* write subaddress, enable auto-increment */ + twWriteRaw ((1 << 7) | twr.subaddress); twFlushRaw (); + ++twr.step; } else { twr.status = TWST_ERR; } @@ -120,8 +101,12 @@ static void twIntWrite () { case 2: if (TW_STATUS == TW_MT_DATA_ACK) { - twWriteRaw (twr.data); + twWriteRaw (twr.data[twr.i]); + ++twr.i; twFlushRaw (); + if (twr.i >= twr.count) { + ++twr.step; + } } else { twr.status = TWST_ERR; } @@ -140,12 +125,11 @@ static void twIntWrite () { printf ("nope\n"); break; } - ++twr.step; } /* handle interrupt, read request */ -static void twIntReadMulti () { +static void twIntRead () { switch (twr.step) { case 0: if (TW_STATUS == TW_START) { @@ -201,7 +185,7 @@ static void twIntReadMulti () { case 5: if (TW_STATUS == TW_MR_DATA_ACK) { - twr.retData[twr.i] = TWDR; + twr.data[twr.i] = TWDR; ++twr.i; if (twr.i < twr.count-1) { /* read another byte, not the last one */ @@ -220,7 +204,7 @@ static void twIntReadMulti () { case 6: if (TW_STATUS == TW_MR_DATA_NACK) { /* receive final byte, send stop */ - twr.retData[twr.i] = TWDR; + twr.data[twr.i] = TWDR; twStopRaw (); twr.status = TWST_OK; } else { @@ -229,7 +213,7 @@ static void twIntReadMulti () { break; default: - printf ("twIntReadMulti: nope\n"); + printf ("twIntRead: nope\n"); break; } } @@ -240,8 +224,8 @@ ISR(TWI_vect) { twIntWrite (); break; - case TWM_READ_MULTI: - twIntReadMulti (); + case TWM_READ: + twIntRead (); break; default: |