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Cleanup of modem filters

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This commit is contained in:
Steve Underwood
2013-03-16 15:35:39 +08:00
parent f368369945
commit 6af84a870c
20 changed files with 606 additions and 621 deletions
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53
libs/spandsp/src/async.c
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@@ -212,42 +212,46 @@ SPAN_DECLARE_NONSTD(int) async_tx_get_bit(void *user_data)
{
async_tx_state_t *s;
int bit;
int parity_bit;
s = (async_tx_state_t *) user_data;
if (s->bitpos == 0)
{
if (s->presend_bits > 0)
{
s->presend_bits--;
return 1;
}
if ((s->byte_in_progress = s->get_byte(s->user_data)) < 0)
{
/* No more data */
bit = SIG_STATUS_END_OF_DATA;
if (s->byte_in_progress != SIG_STATUS_LINK_IDLE)
return s->byte_in_progress;
/* Idle for a bit time. If the get byte call configured a presend
time we might idle for longer. */
return 1;
}
s->byte_in_progress &= (0xFFFF >> (16 - s->data_bits));
if (s->parity != ASYNC_PARITY_NONE)
{
parity_bit = parity8(s->byte_in_progress);
if (s->parity == ASYNC_PARITY_ODD)
parity_bit ^= 1;
s->byte_in_progress |= (parity_bit << s->data_bits);
s->byte_in_progress |= (0xFFFF << (s->data_bits + 1));
}
else
{
/* Start bit */
bit = 0;
s->parity_bit = 0;
s->bitpos++;
s->byte_in_progress |= (0xFFFF << s->data_bits);
}
}
else if (s->bitpos <= s->data_bits)
{
bit = s->byte_in_progress & 1;
s->byte_in_progress >>= 1;
s->parity_bit ^= bit;
s->bitpos++;
}
else if (s->parity && s->bitpos == s->data_bits + 1)
{
if (s->parity == ASYNC_PARITY_ODD)
s->parity_bit ^= 1;
bit = s->parity_bit;
/* Start bit */
bit = 0;
s->bitpos++;
}
else
{
/* Stop bit(s) */
bit = 1;
if (++s->bitpos > s->data_bits + s->stop_bits)
bit = s->byte_in_progress & 1;
s->byte_in_progress >>= 1;
if (++s->bitpos > s->total_bits)
s->bitpos = 0;
}
return bit;
@@ -278,16 +282,15 @@ SPAN_DECLARE(async_tx_state_t *) async_tx_init(async_tx_state_t *s,
flow control does not exist, so V.14 stuffing is not needed. */
s->data_bits = data_bits;
s->parity = parity;
s->stop_bits = stop_bits;
s->total_bits = data_bits + stop_bits;
if (parity != ASYNC_PARITY_NONE)
s->stop_bits++;
s->total_bits++;
s->get_byte = get_byte;
s->user_data = user_data;
s->byte_in_progress = 0;
s->bitpos = 0;
s->parity_bit = 0;
s->presend_bits = 0;
return s;
}