User Manual

MHX-2400 Operating Manual: Appendix C Sample Schematic Diagram 31
C. Sample Schematic Diagram
The following is a sample microprocessor implementation with a MICROCHIP PIC 16C74 and the MHX-2400. The MHX-
2400 performs no level shifting on the serial port, so direct connection to the host microprocessor is possible.
DO NOT CONNECT THE MHX-2400 TO RS 232 DRIVER OUTPUTS. DAMAGE TO THE UNIT MAY RESULT.
On this implementation, the onboard SCI of the PIC 16C74 is directly connected pins 2 and 3 of the MHX-2400. The bi-
directional Port D is used for asserting or monitoring control signals from the MHX-2400.
The RESET and CONFIG signals are momentary active low signals asserted by the host microprocessor.
RESET initializes the MHX-2400 and places the system in a known state. This signal should be set high after the host
microprocessor has been reset.
The CONFIG line is reserved for factory use. This signal should be set high.
RXD
TXD
DCD
DTR
DSR
RTS
CTS
CONFIG
RESET
PIC16C74 MHX-900
2
3
1
4
6
7
8
32
31
Power Connections not shown
RC7
RC6
RD0
RD1
RD2
RD3
RD4
RD5
RD6