From 02d7413ab02af869c52eba954905b2756c9334d8 Mon Sep 17 00:00:00 2001 From: "Eric S. Raymond" Date: Sun, 10 Nov 2013 17:24:02 -0500 Subject: Update a comment with a caveat. --- drivers.c | 23 ++++++++++++++--------- 1 file changed, 14 insertions(+), 9 deletions(-) (limited to 'drivers.c') diff --git a/drivers.c b/drivers.c index a2e07bf9..634f6f50 100644 --- a/drivers.c +++ b/drivers.c @@ -157,16 +157,21 @@ static void nmea_event_hook(struct gps_device_t *session, event_t event) #ifdef SIRF_ENABLE case 1: /* - * We used to try to probe for SiRF by issuing "$PSRF105,1" - * and expecting "$Ack Input105.". But it turns out this - * only works for SiRF-IIs; SiRF-I and SiRF-III don't respond. - * Thus the only reliable probe is to try to flip the SiRF into - * binary mode, cluing in the library to revert it on close. + * We used to try to probe for SiRF by issuing + * "$PSRF105,1" and expecting "$Ack Input105.". But it + * turns out this only works for SiRF-IIs; SiRF-I and + * SiRF-III don't respond. Sadly, the MID132 binary + * request for firmware version is ignored in NMEA mode. + * Thus the only reliable probe is to try to flip the SiRF + * into binary mode, cluing in the library to revert it on + * close. * - * SiRFs dominate the GPS-mouse market, so we used to put this test - * first. Unfortunately this causes problems for gpsctl, as it cannot - * select the NMEA driver without switching the device back to - * binary mode! Fix this if we ever find a nondisruptive probe string. + * SiRFs dominate the consumer-grade GPS-mouse market, so + * we used to put this test first. Unfortunately this + * causes problems for gpsctl, as it cannot select the + * NMEA driver without switching the device back to binary + * mode! Fix this if we ever find a nondisruptive probe + * string. */ gpsd_report(session->context->debug, LOG_PROG, "=> Probing for SiRF\n"); (void)nmea_send(session, -- cgit v1.2.1