AVL AVL DiCom 4000, Service Manual

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Evaluation Unit AVL 4000
4-6 Service Manual
4.2.1.4 Interfaces
All external interfaces are connected directly to the pcbs.
The connection for an external PC keyboard is a standard five-pin plug and is processed
by the 196NT via the timer EPA channels.
An A4 printer can be connected by a 25-pin SUB-MIN-D socket as a standard Centronics
parallel interface.
A TRUART module serves the internal serial interface to the 4-gas measuring instruments
unit in the AVL DiGas and AVL DiCom.
The interface to a host computer (PC, SilverDat computer, Bilanmatik, test bed
computer,…) is also via a standard 9-pin SUB-MIN-D socket and implemented by the
asynchronous serial interface installed in the 196NT. This allows maximum flexibility for
various requirements (such as baud rate, parity check).
Interface socket 9-pin D-sub socket
Interface RS232 serial
Data transfer format 8 bit, 1 stop bit, no parity
Data transfer rate 9600 bit/s
Transfer code ASCII
Pin assignment 1
2
3
4
5 PRG
TxD
RxD
DTR
GND Connected to GND
Transmit data (output)
Receive data (input)
Not used
Ground
6
7
8
9 DSR
RTS
CTS
RI
Not used
Provided the instrument has the requisite software installed, measurement data can be
transmitted via this interface to a computer (Isotec interface). The data is transferred as
ASCII code.
The interface can be set in the service menu under User data/Configuration.
Parameters: 9600 baud, 8 data bits, 1 stop bit, no parity
3…no. of repeats on transfer (= max. 2 repeats)
2 sec. timeout for RS232 (applies to each repeat)
The following operating modes can be selected:
−
MASTER
The instrument transmits a defined data block to the computer at the touch of a
button or after an event. The computer must be ready to receive the data.