Siemens - Festo VIFB-02- Series Manual

VIFB1 - 02
Bit no.
Bit designation BASP
Fig. 6/10: Protocol structure of diagnostic byte
6-12
> IFB1-02_BES_V_018474g1_1996-04N - Restored Document - 2011-12-15 <
6. Diagnostic/error treatment

Siemens

A diagnostic byte is stored in the field bus modu-
le (AS308-3U)
(ET100U). The number of the diagnostic byte
thereby corresponds to the field bus address
(ET100 no.) of the appropriate field bus slave
(valve terminal/valve sensor terminal).
Example:
Reading the diagnostic byte.
Program:
L KB n 'n =
T PY m 'm =
L PY m 'Transfer diagnostic byte to
T MB xx 'Address xx
Protocol form for diagnostic byte:
7 6 5
0 0
for every field
Field bus address (ET100 no.)
Address in range 128 ... 255,
Recommendation: 254
4 3 2
F4 F3 F2
bus slave
1 0
F1 F0
9604