Rockbox mail archive
Subject: [question] prescanning fm radio frequencies
[question] prescanning fm radio frequencies
-- Hi there.
A question about prescanning of FM Radio.
I use Philips TEA5767HN and 32.768KHz Xtal,
To check the designated frequency is tuned, following part will be
referenced,
int philips_get(int setting)
{
...ommitted...
case RADIO_TUNED:
val = 0;
if (read_bytes[0] & 0x80) /* ready */
{
val = read_bytes[2] & 0x7F; /* IF counter */
val = (abs(val - 0x36) < 2); /* close match */
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
}
break;
...ommitted...
}
I hope someone may explain this underlined line and the digits(what 0x36
and 2 mean).
This routine can catch the clear frequencies normally.
However it can miss the clear ones many times too.
Thanks
mipsan
/////////////////////////////////////////////////
// //
// WHY NOT !!! LET'S TRY !!! //
// //
// mipsan@gmail.com //
// //
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Received on Tue Jun 7 04:18:16 2005
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