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Major formatting/whitespace cleanup

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px4dev
2012-10-23 23:51:13 -07:00
parent 34f99c7dca
commit 2fc1032069
50 changed files with 1112 additions and 810 deletions
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apps/systemlib/ppm_decode.c
+15 -9
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@@ -30,7 +30,7 @@
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/**
* @file ppm_decode.c
*
@@ -51,7 +51,7 @@
*
* The PPM decoder works as follows.
*
* Initially, the decoder waits in the UNSYNCH state for two edges
* Initially, the decoder waits in the UNSYNCH state for two edges
* separated by PPM_MIN_START. Once the second edge is detected,
* the decoder moves to the ARM state.
*
@@ -64,9 +64,9 @@
*
* The ACTIVE state expects an edge within PPM_MAX_PULSE_WIDTH, and when
* received calculates the time from the previous mark and records
* this time as the value for the next channel.
* this time as the value for the next channel.
*
* If at any time waiting for an edge, the delay from the previous edge
* If at any time waiting for an edge, the delay from the previous edge
* exceeds PPM_MIN_START the frame is deemed to have ended and the recorded
* values are advertised to clients.
*/
@@ -132,21 +132,23 @@ ppm_input_decode(bool reset, unsigned count)
/* how long since the last edge? */
width = count - ppm.last_edge;
if (count < ppm.last_edge)
width += ppm.count_max; /* handle wrapped count */
ppm.last_edge = count;
/*
/*
* If this looks like a start pulse, then push the last set of values
* and reset the state machine.
*
* Note that this is not a "high performance" design; it implies a whole
* frame of latency between the pulses being received and their being
* frame of latency between the pulses being received and their being
* considered valid.
*/
if (width >= PPM_MIN_START) {
/*
/*
* If the number of channels changes unexpectedly, we don't want
* to just immediately jump on the new count as it may be a result
* of noise or dropped edges. Instead, take a few frames to settle.
@@ -169,11 +171,13 @@ ppm_input_decode(bool reset, unsigned count)
ppm_decoded_channels = new_channel_count;
new_channel_count = 0;
}
} else {
/* frame channel count matches expected, let's use it */
if (ppm.next_channel > PPM_MIN_CHANNELS) {
for (i = 0; i < ppm.next_channel; i++)
ppm_buffer[i] = ppm_temp_buffer[i];
ppm_last_valid_decode = hrt_absolute_time();
}
}
@@ -193,10 +197,11 @@ ppm_input_decode(bool reset, unsigned count)
return;
case ARM:
/* we expect a pulse giving us the first mark */
if (width > PPM_MAX_PULSE_WIDTH)
goto error; /* pulse was too long */
/* record the mark timing, expect an inactive edge */
ppm.last_mark = count;
ppm.phase = INACTIVE;
@@ -211,6 +216,7 @@ ppm_input_decode(bool reset, unsigned count)
return;
case ACTIVE:
/* we expect a well-formed pulse */
if (width > PPM_MAX_PULSE_WIDTH)
goto error; /* pulse was too long */
@@ -228,7 +234,7 @@ ppm_input_decode(bool reset, unsigned count)
ppm_temp_buffer[ppm.next_channel++] = interval;
ppm.phase = INACTIVE;
return;
return;
}