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11 FUNCTIONS ACCESSIBLE TROUGH THE RS232 INTERFACE
Both TT80 and TT90 operate based on 2 communication modes using the same transmis-
sion format, i.e. :
Data rate 4800 bauds
ASCII code 7 bits
Start 1 bit
Stop 2 bits
Parity even
11.1 Monodirectional data transmission
In this mode, the standard cable 04761046 is used. Transfer of a character or a BREAK,
or changes to the DTR status line causes displayed value to be sent back.
Data transfer
TT80 and TT90 in TT80 mode TT90 and TT90-UPC
Mm : ±xxxx.xx <cr/lf> µm : ±xxx.xxx <cr/lf>
In : ±.xxxxxx <cr/lf> mil : ±(x)x.xxxx(x) <cr/lf>
11.2 Bidirectional data transmission
This mode uses the standard cable 04761049, allowing the instru-
ment to be controlled over a host computer as instructed (see on
the following page).
50 ms < t < 500 ms
Data Request (DTR)
Data (RXD)
+
–
OV
+
–
OV
5
V+ (DTR)
Data In (TXD)
Data Out (RXD)
1
9
V– (RTS)
6
5
Data Request (DTR)
V-(TXD)
Data Out (RXD)
1
9
V+(RTS)
6
TESA SPC printer or Sub-D
connector 9-pin/m on PC
5
V+ (DTR)
Data In (TXD)
Data Out (RXD)
1
9
V– (RTS)
6
5
Data Request (DTR)
V-(TXD)
Data Out (RXD)
1
9
V+(RTS)
6
TESA SPC printer or Sub-D
connector 9-pin/m on PC