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authorLars-Dominik Braun <lars@6xq.net>2014-03-31 11:18:32 +0200
committerLars-Dominik Braun <lars@6xq.net>2014-04-22 16:51:13 +0200
commite3897565c342bee4765f921240b7ca91cd9b23f1 (patch)
treee7e328ee9452d54db9cfe66cccdb031cb704030f /i2c.c
parent24d11d4976062e965fb64861808548c39f53714b (diff)
downloadhourglass-e3897565c342bee4765f921240b7ca91cd9b23f1.tar.gz
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Activate accel + timer
Diffstat (limited to 'i2c.c')
-rw-r--r--i2c.c24
1 files changed, 16 insertions, 8 deletions
diff --git a/i2c.c b/i2c.c
index ef2392e..57ee551 100644
--- a/i2c.c
+++ b/i2c.c
@@ -68,7 +68,7 @@ bool twRequest (const twMode mode, const uint8_t address,
twr.step = 0;
twr.status = TWST_WAIT;
/* wait for stop finish; there is no interrupt generated for this */
- while (TW_STATUS != 0xf8);
+ while (TW_STATUS != 0xf8 || TWCR & (1 << TWSTO));
twStartRaw ();
return true;
@@ -130,62 +130,68 @@ static void twIntWrite () {
/* handle interrupt, read request
*/
static void twIntRead () {
+ uint8_t status = TW_STATUS;
switch (twr.step) {
case 0:
- if (TW_STATUS == TW_START) {
+ if (status == TW_START) {
/* write device address */
twWriteRaw (twr.address | TW_WRITE);
twFlushRaw ();
++twr.step;
} else {
twr.status = TWST_ERR;
+ twr.error = status;
}
break;
case 1:
- if (TW_STATUS == TW_MT_SLA_ACK) {
+ if (status == TW_MT_SLA_ACK) {
/* write subaddress, enable auto-increment */
twWriteRaw ((1 << 7) | twr.subaddress);
twFlushRaw ();
++twr.step;
} else {
twr.status = TWST_ERR;
+ twr.error = status;
}
break;
case 2:
- if (TW_STATUS == TW_MT_DATA_ACK) {
+ if (status == TW_MT_DATA_ACK) {
/* send repeated start */
twStartRaw ();
++twr.step;
} else {
twr.status = TWST_ERR;
+ twr.error = status;
}
break;
case 3:
- if (TW_STATUS == TW_REP_START) {
+ if (status == TW_REP_START) {
/* now start the actual read request */
twWriteRaw (twr.address | TW_READ);
twFlushRaw ();
++twr.step;
} else {
twr.status = TWST_ERR;
+ twr.error = status;
}
break;
case 4:
- if (TW_STATUS == TW_MR_SLA_ACK) {
+ if (status == TW_MR_SLA_ACK) {
/* send master ack if next data block is received */
twFlushContRaw ();
++twr.step;
} else {
twr.status = TWST_ERR;
+ twr.error = status;
}
break;
case 5:
- if (TW_STATUS == TW_MR_DATA_ACK) {
+ if (status == TW_MR_DATA_ACK) {
twr.data[twr.i] = TWDR;
++twr.i;
if (twr.i < twr.count-1) {
@@ -199,17 +205,19 @@ static void twIntRead () {
}
} else {
twr.status = TWST_ERR;
+ twr.error = status;
}
break;
case 6:
- if (TW_STATUS == TW_MR_DATA_NACK) {
+ if (status == TW_MR_DATA_NACK) {
/* receive final byte, send stop */
twr.data[twr.i] = TWDR;
twStopRaw ();
twr.status = TWST_OK;
} else {
twr.status = TWST_ERR;
+ twr.error = status;
}
break;