doc: Document LEDs on TeleGPS devices

V1 has just the battery charger. V2 adds the GPS lock indicator.

Signed-off-by: Keith Packard <keithp@keithp.com>

diff --git a/doc/telegps-using.inc b/doc/telegps-using.inc
index 1dd889cda8b37e0f6d8234f89ef2298f02f2fd3f..b21445fce6e92931d266714409ea2d51a1d623a1 100644 (file)
--- a/doc/telegps-using.inc
+++ b/doc/telegps-using.inc
@@ -52,7 +52,24 @@
                onboard flash before it fills up. TeleGPS will still
                report telemetry even if memory is full, so the only
                thing you will lose is the on-board data log.
-      
+
+       === LEDs
+
+               TeleGPS v1.0 has a dual greed/red LED along the edge
+               towards the USB connector end of the board. This
+               indicates battery charging status while connected to
+               power over USB. When the red LED is lit, the battery
+               is charging. Once the battery is fully charged, the
+               red LED goes out and the green LED turns on. If both
+               LEDs are lit, something is probably wrong with the battery.
+
+               TeleGPS v2.0 has the same green/red battery charging
+               status LED and adds another green LED along the same
+               edge, towards end of the board with the 70cm
+               antenna. This green LED indicates GPS lock status — it
+               blinks once every three seconds when the GPS receiver
+               is locked and tracking position.
+
        === Installation
 
                The battery connectors are a standard 2-pin JST