User Manual

MPH DS4 Radar Interface

Protocol Document

1. Speed Packet Protocol

The DS4 Radar message packet consists of 7 bytes @ 1200 baud, no parity, 8

data bits, 1 start bit. Messages are paced at 250mS intervals and are sent

whether there is a target or not.

Char Description

1 <STX> Start of message

2 Status Radar status, as defined below

3 Not used

4 Approaching Target Speed values below 4 are treated as zero.

5 Reserved

6 Target Range/10 Values below 4 are treated as zero

7 <ETX> End of message

1.1. Radar status byte

Bit Description/function if set

0 Low voltage error

1 Not used

2 Not used

3 Not used

4 Not used

5 Always zero

6 Always zero

7 Always set

1.2. Example

Received sequence 02, 128(0x80), 01, 65, 01, 55, 03.

Strongest approaching target at 65 at a range of 550 feet.