ANDE TELEMETRY DEFINITIONS AND EQUATIONS Rev-1 13 Oct 2006 -------------------------------------------------------------------- The 20 channels of ANDE telemetry are multiplexed into 4 sequential frames. Each frame consists of 5 analog channels, and 8 status bits which include the two FRAME counter bits. It takes 4 frames to constitute the complete telemetry picture of ANDE. Frame Format: ANDE>BEACON,SGATE:T#SSS,111,222,333,444,555,FF111111 Where the header is ANDE>BEACON,SGATE: (These fields may vary) Within the actual data portion of the packet are these fields: SSS is the serial number 111 is the first channel telemetry 222 is the second channel 333 is the third channel 444 is the forth channel 555 is the fifth channel FF111111 the 8 internal bits (including the FRAME counter) FF CHANNEL 1 CHANNEL 2 CHANNEL 3 CHANNEL 4 CHANNEL 5 -- ----------- ---------- ---------- ---------- ---------- 11 BUS-Volts SOLAR-X SOLAR-Y SOLAR-Z 5V BUS 10 Temp-BAT Temp-SOL-X Temp-SOL-Y Temp-SOL-Z Temp-Retro 01 Laser-Volts A1-Amps A2-Amps B1-Amps B2-Amps 00 Temp-Bat-B Clock Temp-Laser Time-to-Go On-Time Telemetry equations are generally of the form y = aX + b where X is the 3 byte decimal telemetry count in each channel in the data. Temperature is a cubic y=aX^3 + bX^2 + cX - d. Define Function for Temperature: Tof(V) = .00001 * X ^ 3 - .0039 * X ^ 2 + .829 * X - 40.4 IF Frame is "00" THEN Temp-Bat-B = TempOf(X1) Clock = X2 * 1 Temp-Laser = TempOf(X3) Time-to-Go = X4 * 1 On-Time = X5 * 1 IF Frame is "01" THEN Laser Volts = X1 * 0.1 A1-Amps = X2 * 1.7 - 4 A2-Amps = X3 * 1.7 - 4 B1-Amps = X4 * 1.7 - 4 B2-Amps = X5 * 1.7 - 4 IF Frame is "10" THEN Temp-Bat-A = TempOf(X1) Temp-SOL-X = TempOf(X2) Temp-SOL-Y = TempOf(X3) Temp-SOL-Z = TempOf(X4) Temp-Retro = TempOf(X5) IF Frame is "11" THEN BUS-volts = X1 * 0.1 SOL-X = X2 * -.0196 + 1 SOL-Y = X3 * -.0196 + 1 SOL-Z = X4 * -.0196 + 1 5-volt-ref = X5 * .0235 de WB4APR, Bob