Steren GPS-500 Manual De Instrucciones página 22

I/O interface
The I/O interface has fi ve pins, and each pin function is described as
below.
1
Pin
1 VCC IN (DC 5.4 ± 0.2 1A)
Serial Data output port A (TTL
2
Level ； Voh ≧ 2.4V, Vol ≦ 0.4V;
3
Serial Data input port A(TTL
Level ； Vih ≧ 0.7*VCC ； Vil ≦ 0.3*VCC)
4
Outside device (Reserve of software
5
program definition.)
ENGLISH-22
4
3
2
Function
TX
Ioh=Iol=2mA)
RX
GND
5