Operation
62
GA 09.033/6.02 – (2011-07) –
©
Oerlikon Leybold Vacuum
Definitions
The following abbreviations and symbols are used:
Symbol Meaning
HOST
Computer or terminal
[...] Optional
elements
ASCII
American Standard Code for Information In-
terchange
Dec Hex
<ETX> END OF TEXT (CTRL C)
Reset the interface
3 03
<CR> CARRIAGE
RETURN
Go to beginning of the line
13 0D
<LF> LINE
FEED
Advance by one line
10 0A
<ENQ> ENQUIRY
Request for data transmission
5 05
<ACK> ACKNOWLEDGE
Positive report signal
6 06
<NAK> NEGATIVE
ACKNOWLEDGE
Negative report signal
21 15
"Transmit":
Data transfer from HOST to CENTER
ONE.
"Receive":
Data transfer from CENTER ONE to
HOST.
Format of pressure values
For pressure values, the following format is used:
sx.xxxxEsxx
│
│
│└───
Exponent
│
│
└────
Sign exponent
│
└───────
-
──
Mantissa
└────
-
────
-
──
Sign mantissa
Flow Control
After each ASCII string, the HOST must wait for a report
signal (<ACK><CR><LF> or <NAK> <CR><LF>).
The input buffer of the HOST must have a capacity of at
least 25 bytes.
