Matrix Orbital GTT43A - Manual (Page 12)

GTT43A Hardware Manual 8
4.2 I 2 C Communication/Power Header
A dedicated I
2
C header is available on all GTT43A models and provides the most basic protocol
connection to the unit.
Figure 12: I
2
C Communication/Power Header
Table 7: I
2
C Communication/Power Pinout
Pin Function
1 Vcc
2 SCL
3 SDA
4 Gnd
Voltage is applied through pins one and four of the header, please reference the electrical specifications
before applying power. Pins two and three are reserved for I
2 C clock and data signals respectively, both
of which should be pulled up to five volts using a resistance between one and ten kilohms. The Tyco
640456-4-LF style header used can be mated to a number of connectors, including Molex 22-01-3047.
4.3 RS422 Header
RS422 communication provides an industrial alternative to the standard RS232 communication protocol.
Rather than single receive and transmit lines, the RS422 model uses a differential pair for each receive
and transmit signals to reduce degradation and increase transmission lengths.
Figure 13: RS422 Header
Table 8: RS422 Pinout
Pin Function
1 Vcc
2 Tx (A)
3 Inv Tx (B)
4 * Inv Rx (Z)
5 * Rx (Y)
6 Gnd
The six pin RS422 Header offers a power and ground connections at either end, and two differential pair
communication lines in the middle. Regular and inverted lines, labelled A/B and Z/Y, are provided for
receive and transmit signals. The standard Tyco 282834-6 style header populated is best mated to a
sized 16 to 30 on the American Wire Gauge connections that are secured via the header screws.
*Note: Changes made in PCB Rev. 2.2, prior to Rev. 2.2 Pin 4 was Rx (Y) and Pin 5 was Inv Rx (Z).