Genicom 3600 Communications Interface, Converter, DIP Switches, Asic and I/O Option Interface

3600 Printer Maintenance Manual

Communications Interface

The communications interface for the 3600 follows the Intermec Standard Data Connector standard. J1 is a 25 pin D-sub connector that supports both RS-232 and RS-485 interfaces. U1 is the RS-485 driver/receiver and U22 and U4 are the RS-232 driver and receivers. To further enhance the interface to support DTR/RTS flow control, the DTR pin is driven with the PIN 14 signal. This arrangement allows the use of standard cables for hardware flow control, which enables the user to use commands such as the DOS COPY command from any PC. Zero ohm resistors have been incorporated into the RS-232 driver outputs so that the previous configuration or other configurations are possible.

A/D Converter

The Motorola MC145041 A/D converter is an 11-channel, 8-bit, serial A/D converter. The reference is set to +5V. Seven of the eleven channels are used:

Channel	Function
0	Label gap sensor
1	Darkness adjust
2	Printhead thermistor
3	Label mark sensor
4	+40V
5	Printhead voltage, +24V
6	Label taken sensor

The A/D converter is continuously communicating with the MC68332 through the SPI. It receives conversion commands and channel addresses while sending back results from the previous command. The clock rate for the MC145041 is 1 MHz.

DIP Switches

The 3600 has 16 DIP switches to provide configuration and test and service operation.

ASIC and I/O Option Interface

The 3600 uses an Intermec designed thermal compensation ASIC. This ASIC handles the loading of the printhead to implement the dot-by-dot thermal management scheme.

Address/Data Multiplexor

Since both the ASIC and the I/O option interfaces are designed to interface with a processor that has multiplexed address and data, it is necessary to multiplex the address and data from the MC68332. ICs U14 and U15 are used to route address or data to the AD (0:7) bus.

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