Gasboy TopKAT Operation Manual - Manual (Page 20)

System Overview Communications
Page 12 MDE-4338A TopKAT™ Fuel Management System Operation Manual · February 2009
Battery Maintenance/Replacement
Check Battery Low LED periodically. If lit, replace the battery using the following procedure.
Do not turn off system power! This could cause irrevocable loss of data.
CAUTION
1 Insert a new battery, C09415, into the empty battery receptacle on the CPU PCB.
2 Remove the old battery from its battery receptacle. Battery Low (Amber) LED should go out.
Communications
Communications Ports
The TopKAT contains three asynchronous ports:
• Port 1 is used for communications to the 9800, mechanical PCU, and satellites via RS-485
lines.
• Ports 2 and 3 can be set for either RS-232 or RS-422 communications to a data terminal or
computer. If used with the 9800, wiring restrictions dictate that only one of these two ports
can be used for terminal/computer communication, unless Port 3 is connected to an
internal modem. The 9820 ASTRA and the mechanical PCU option have no wiring
restrictions.
MDE-4340/MDE-4341 Series 9800 Q/A Installation/Operation Manual, MDE-4319 TopKAT
Installation Manual, MDE-4331 Atlas
™ Fuel Systems Installation Manual, and MDE-4520
Enhanced Communications Installation Manual contain detailed communication requirements
for port wiring and exceptions. Communication is through direct wire, by dial-up phone lines
using an optional internal modem, by serial-to-LAN connection, or wireless communications.
Communications Protocol
Devices that communicate with the TopKAT must be able to transmit and receive full duplex,
ASCII asynchronous data via an EIA RS-232 connection.
The TopKAT supports both a simple and a structured computer protocol. With the simple
terminal protocol, no special characters are transmitted to designate the beginning or end of
data blocks. Data is transmitted in serial bit format per character as follows: one start bit, eight
data bits, one stop bit. Each character is echoed back to the transmitting device. This checks
the integrity and enables the CRT operators to display transmitted data.
The structured computer protocol is covered in a separate manual, C35965 TopKAT Host
Communications Manual.