Trans-Cal SSD120-N-RS5, Owners & Installation Manual, Page: 10 / 57

1.8.7 One-Foot Resolution Protocol
Leaving pins 9 and 10 of the DA-15S serial data receptacle open, the one-foot resolution
protocol
MUST
be software selected see
§4.8
for protocol selection details. Once selected,
the Digitizer will send a seventeen byte message beginning with RMS, then a space
followed by a sign, five altitude bytes; the letter “T” and the temperature sign; the number
“55”; two checksum bytes and a carriage return. (9600bps, 8 data bits, 1 stop bit, no
parity). The following is an example of the one-foot resolution altitude message:
Message Definition
RMS +55C2
C
R
Pressure Altitude 859 feet
This message is transmitted on TxD4 (pin 14) and TxD5 (Pin 15) ONLY!
The remaining serial ports TxD1 (pin 6), TxD2 (Pin 8) and TxD3 (pin 12) will transmit the
protocol assigned via software or via the jumpers on the serial data receptacle DA-15S.
SERI AL DATA
RECEPTACLE DA-15S
PARALLEL DATA AND POWER
CONNECTOR DA-15P
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