APPENDIX
P-7
Digital Interface
(IEC 61162-1 Edition 2 (2000-07)/ IEC 61162-2(1998-09))
Sentence data
Input sentences
ABM, ACA, ACK, AIR, BBM, DTM, GBS, GGA, GLL, GNS, HDT, LRF, LRI, OSD, RMC,
ROT, SSD, VBW, VSD, VTG
Output sentences
ABK, ACA, ALR, LRF, LR1, LR2, LR3, TXT, VDM, VDO
Transmission interval
ABK: With each event
ACA: At RX
ALR: 30 s during alarm, 2 min normally no alarm
LRF, LR1, LR2, LR3: At RX
TXT: Each update
VDM: At RX
VDO: 1 s
Load requirements as listener
Isolation: Provided
Input Impedance: 190 ohms (940 ohms without jumper plug)
Max. Voltage: ±14 V to GNDiso
Threshold: ±0.2 V (A-B)
Data transmission
Data is transmitted in serial asynchronous form in accordance with the standard
referenced in 2.1 of IEC 61162-1/2. The first bit is a start bit and is followed by data bits,
least-significant-bit as illustrated below.
The following parameters are used:
Baud rate: 38.4 Kbps /4800 bps
Data bits: 8 (D7 = 0), parity none
Stop bits: 1
D0D1D2D3D4D5D6D7
Start
bit
Stop
bit
Databits