Applies To:
  • CitectSCADA 1.00 1.01 1.10 1.11 1.20 2.00 2.01

Question: When I startup Citect, the computer will hang when it is initialising the PCXi Digiboard. If I remove the configuration of the Digiboard Citect will startup OK. What am I doing wrong? 

You are getting a clash from the Digiboard and some other piece of hardware. This can be caused if the Digiboard is using the same interrupt as another card, or the same memory address as another card, or by not excluding the digiboards memory correctly. Check the interrupt and memory usage of all cards in the computer (by running the MSD program from a DOS prompt). Make sure that all cards are using unique interrupt numbers and memory addresses. If you are not sure, try removing all other cards from the computer and see if Citect will run OK. If Citect then runs OK, put back each card until Citect will no longer run and you have found the clashing card.

The memory addresses of the Digiboard must also be excluded correctly or Windows will crash when Citect tries to initialise the Digiboard. If you have a Extended Memory Manager (eg EMM386 QEMM386 or CEMM) loaded in the CONFIG.SYS file, you must specify an exclude region. For example if you have a PCXI Digiboard at address D000 and EMM386 driver, you must use the X option to exclude the memory from D000 to DFFF as follows:


If you have a COMXi Digiboard at memory address C800 to CFFF the command would look like:


You must also exclude the memory in the SYSTEM.INI with the EMMExclude option (under the 386Enh section). For the PCXi Digiboard at memory address, D000 put the following exclude under the 386Enh section:


If you have a COMXi Digiboard at memory address C800 to CFFF the command would look like:


See your MS-DOS or Windows documentation for full details on how to exclude memory correctly for your particular extended memory driver..