To synchronize simultaneous Start and Stop, it is recommended to connect the GO-lines, pin 9 of the feature connector, see Fig 3.6
in the manual, and cross the checkboxes "Watch", "High at Start", "Low at Stop", see Fig. 5.13.

To synchronize the clocks, it is recommended to operate one MCS8A with external clock provided by the other one, by connecting the Ref Clk
connectors. External clock can be specified either in the mcs8.ini file or in the
"Test, Inspect" Dialog, Fig. 5.7.

For synchronizing up to 8 modules we offer the Eight output START trigger / master clock source  MCCD, see the "application" tab of

www.fastcomtec.com/ufm/mccd