INFICON MDC-370 Thin Film Deposition Controller - Manual (Page 131)

MDC-370 DEPOSITION CONTROLLER
11. COMPUTER INTERFACE
11.1 GENERAL
The various computer interfaces of the Maxtek MDC-370 Deposition Controllers
permit complete remote control using a personal computer. There are three types
of computer interfaces offered. The MDC-370 comes standard with an RS-232
serial interface. Both RS-485 and IEEE-488 interfaces are available as options.
11.2 RS-232 SERIAL INTERFACE
The standard RS-232 serial interface of the MDC-370 allows one 370 to be
connected to any other device with as RS-232 serial interface. There are two
connections for the RS-232 interface port. A D9P connector is provided on the
rear panel for permanent connection to the host computer. The pin layout is
shown in Figure 8-5 and Table 8-3 lists pin signal assignments, including a
definition of whether the signal is an output from the MDC-370 or an input to the
MDC-370.
A DJ11 jack located on the front panel is provided for temporary connection to
the host computer. Pin layout and pin signal assignments are shown in Figure
8-7 and Table 8-5.
The MDC-370 acts as DTE, and accordingly the 9-pin connector has ‘plug’ pins.
It should be connected to the host computer via a straight 9-pin female to 9-pin
female cable. Straight means pin 1 is connected to pin 1, pin 2 to pin 2, etc.
In the case where a special cable is required, remember to observe the sense of the
RxD/TxD data lines and the control lines. Pin 2 ‘TxD’ transmits data from the
MDC-370 to the host; pin 3 ‘RxD’ receives data from the host. Pin 7 ‘CTS’ is a
control input signal, and pin 8 ‘RTS’ is a control output signal.
In this implementation, pin 7 ‘CTS’ means what is says, namely, this is an input
control line to the 370 which must be asserted ‘true’ before the 370 is clear to
send data to the host. Pin 8 ‘RTS’ is an output from the 370 indicating to the host
that the 370 is ready to receive data from the host. The MDC-370 will always
assert RTS 'true' unless its input buffer is full from too much incoming data.
The MDC-370’s RS-232 port is automatically set up to operate with the following
specifications:
9600 Baud, 8 Bit data, No Parity, 1 Stop bit
11.3 RS-485 SERIAL INTERFACE
The optional RS-485 serial interface of the MDC-370 allows connection to up to
32 separate devices equipped with RS-485. The RS-485 serial interface is also
ideal in electrically noisy environments and in applications where long cables are
required. The RS-485 port of the MDC-370 is the same D9P connector on the
rear panel used for RS-232. The pin layout is shown in Figure 8-5 and Table 8-3
COMPUTER INTERFACE 11-1