Functions Of The Serial Interface; Technical Data Of Serial Interface V24; Operating The Pocket Keyboard; Basic Command Structure - Bosch ETT 008.31 Repair Instructions

9

Functions of the serial interface

9.1

Technical data of serial interface V24

Pin assignment:
Pin Signal
1 Shield
2 RXD
3 TXD
7 0 V/V24
20 DSR
Number of characters per line for printout = 20 characters
! Ensure the correct setting for the printer! See Section 4.1.11.
9.2 Operating the pocket keypad
! Ensure the correct setting for the keypad! See Section 4.1.12.
The pocket keypad is required for entering the language, the date and the time, and for entering the necessary information in the name
field of the printer log.
i The keypad must be connected to the serial interface V24 (printer connector) of the exhaust-gas analyzer.
The exhaust-gas analyzer sends received characters back to the keypad using the so-called echo principle.

9.2.1 Basic command structure

1st character: "CR" starts data communication, "*CODE:" prompts you to enter a command code.
2nd character: Command code. Only "D", "N" and "S" are permitted.
"S" – CR initiates input procedure for "Language". See Section 9.2.2.
"N" – CR initiates input procedure for "Name field entry". See Section 9.2.3.
"D" – CR initiates input procedure for "Date/time entry". See Section 9.2.4.
"CR" at this point ends data communication.
An incorrect entry here is interrupted by a renewed prompt "*CODE:".
Control character: DEL "Delete" enables the character last entered to be deleted.
LF "Line Feed" causes CR + LF to be executed. Only required for entries in the name field, forwards paper in printer
to a new line during printout.
52
Printer log
1200 baud
1 Start bit
8 Data bits
no parity bit
2 stop bits
Entry, CR
End, or