From 1f0b7bc595ee3df02550ec3ea91f24e43d166fff Mon Sep 17 00:00:00 2001 From: "Eric S. Raymond" Date: Mon, 4 Dec 2006 05:21:11 +0000 Subject: Make the code for Magnavox-format output work again... ...though it's still not hooked up to anything in rtcmdecode(). --- isgps.c | 32 ++++++++++++++++++++++++++++++++ 1 file changed, 32 insertions(+) (limited to 'isgps.c') diff --git a/isgps.c b/isgps.c index 197e552d..92537c1f 100644 --- a/isgps.c +++ b/isgps.c @@ -305,3 +305,35 @@ enum isgpsstat_t isgps_decode(struct gps_packet_t *session, return ISGPS_NO_SYNC; } /*@ +usereleased +compdef @*/ + +/* + * ISGPS data words are 30-bit words. We will lay them into memory into + * 30-bit (low-end justified) chunks. To write them out we will write + * 5 Magnavox-format bytes where the low 6-bits of the byte are 6-bits + * of the 30-word msg. + */ +void isgps_output_magnavox(isgps30bits_t *ip, unsigned int len, FILE *fp) +/* ship an RTCM message to standard output in Magnavox format */ +{ + static isgps30bits_t w = 0; + + while (len-- > 0) { + w <<= 30; + w |= *ip++ & W_DATA_MASK; + + w |= isgps_parity(w); + + /* weird-assed inversion */ + if (w & P_30_MASK) + w ^= W_DATA_MASK; + + /* msb first */ + /*@ -type @*/ + (void)fputc(MAG_TAG_DATA | reverse_bits[(w >> 24) & 0x3f], fp); + (void)fputc(MAG_TAG_DATA | reverse_bits[(w >> 18) & 0x3f], fp); + (void)fputc(MAG_TAG_DATA | reverse_bits[(w >> 12) & 0x3f], fp); + (void)fputc(MAG_TAG_DATA | reverse_bits[(w >> 6) & 0x3f], fp); + (void)fputc(MAG_TAG_DATA | reverse_bits[(w) & 0x3f], fp); + /*@ +type @*/ + } +} -- cgit v1.2.1