TD220MAX_manual_v11.doc
05-6906A01
Page 6 of 49
7/31/2014
3 Interfaces
3.1 Data Interface (DB-25)
The Data Interface has several ports integrated into one connector: Ethernet, COM1 and COM2
Serial Ports, and GPS signaling. Note that COM3 is connected internally and therefore not available
on pins labeled with “COM3.”
DB-25
Pin
Signal
Direction WRT MDS
Equipment
Notes
1
COM3_DCD
Input
Reserved
2
COM2_TXD
Input
GPS NMEA Data Expected
3
COM2_RXD
Output
4
COM2_RTS
Input
5
COM2_CTS
Output
6
COM3_TXD
Output
Reserved
7
GND
Input/Output
8
COM2_DCD
Output
Used for aggregated alarm output, negative
voltage = no alarm, 0 voltage = radio off,
positive voltage = ALARM PRESENT. RS-232
Levels.
9
COM3_CTS
Input
Reserved
10
COM3_RTS
Output
Reserved
11
COM3_DTR
Output
Reserved
12
COM3_RXD
Input
Reserved
13
GND
Input/Output
14
ETH_TX_H
Output
15
ETH_TX_L
Output
16
ETH_RX_H
Input
17
ETH_RX_L
Input
18
EXT_KEY
Output
Reserved
19
EXT_DET
Input
Reserved
20
COM2_DTR
Input
21
ALARM_OUT
Output
Reserved
22
GPS_PPS_L
Input
Not Connected
23
GPS_PPS_H
Input
TTL level 1PPS signal input. 0 to 5 VDC nominal.
24
COM1_RXD
Input
Console
25
COM1_TXD
Output
Console
The DB-25 connector is female, and the orientation of the connector as looking into the front panel
of the unit is as shown below.
12
11
10
9
8
7
6
5
4
3
2
1
24
23
22
21
20
19
18
17
16
15
14
13
25
