ANDE TELEMETRY 4 Sept 2003 ------------------------------------------------------------------- ANDE uses the same telemetry frame format as used by PCsat which consists of a packet header, serial number counter and then five channels of 8 bit decimal telemetry followed by 8 on/off status bits. The 5 channel A/D converters are multiplexed to 4 banks of five telemetry channels each for a total of 20 channels. Routine telemetry is transmitted once a minute whenever ANDE is over a ground station or users. The banks are switched every 45 seconds or so, so that in 4 minutes, we see all 4 banks. The ANDE Telemetry Frame Format is the standard APRS format as shown below: ANDE>APRS,SGATE:T#nnn,CH1,CH2,CH3,CH4,CH5,xxxxxxxx Where: ANDE - AX.25 callsign of ANDE APRS - AX.25 generic TOCALL SGATE - digipeater address for Internet Gateways T#nnn - a 3 decimal digit serial number CH1 to CH5 - 5 telemety channels (3 digit decimal) xxxxxxxx - an 8 byte (8 bit binary) number showing the state of the output bits The telemetry multiplexer can feed any of the four banks of telemetry channels to the standard format as shown below: FRAME 00: CH1 - 8v Regulator Voltage CH2 - X arrays solar current CH3 - Y arrays solar current CH4 - Z arrays Solar current CH5 - 5v Reference voltage FRAME 01: CH1 - Laser Battery voltage CH2 - Battery A1 current CH3 - Battery A2 current CH4 - Battery B1 current CH5 - Battery B2 current FRAME 10: CH1 - Temperature Battery A CH2 - Temperature Solar cell 1 CH3 - Temperature Solar cell 2 CH4 - Temperature Solar cell 3 CH5 - Temperature Retro Reflector 1 FRAME 11: CH1 - Temperature Battery B CH2 - Sleep Timer clock phase CH3 - LASER Temperature CH4 - Time-to-Go (how much of the 1 minute timer remains CH5 - Run-time-counter (25.5 hours max) Since ANDE cold boots from sleep mode on each pass, the serial number will only show counts from the start of each pass and will have no long term significance. The Communications run-time counter is modulo 25.5 hours of ON time. This should give an expected end-around count is every 10 days or so of anticipated operations.