Specifications

ST900 Family General Handbook
667/HB/32900/000 Issue 11 Page 238 of 265
the OMU to monitor the controller’s inputs and lamps without the need for any other
cables. See the description of the enhanced serial link in the Gemini
2
handbook,
With a combined Siemens Gemini
2
and MOVA unit, the control and reply bits
between the ST900 and MOVA are also passed through this link so no digital I/O
cables are required. Also, all the MOVA detectors are only connected to the
controller and passed to MOVA through this serial link.
The layout of the control and reply words should be configured as normal, with F1
starting at control bit 0 and G1 starting at reply bit 0. However the ‘TO’ (take-over)
and ‘CRB’ (controller reply bit) bits should be excluded since they are automatically
passed between the controller firmware and the MOVA firmware as unique bits and
thus do not appear in the normal control and reply words.