Tech Support - FAQ - C1900 - 13

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    Question: My instrument will not recognize the new I/O Card, It only displays a "0". Why is this?

    Answer (A): If installing the original design I/O (C1900-0255: See pictures below), The "0" display is an indication that the C1900 does not acknowledge the installed I/O card. First check and make sure all pins are properly seated in the expansion socket. If they are, then it is likely that the I/O card is in need of repair and/or needs to be commissioned before use.

    Answer (B): A new design I/O Card (C1900-0405: See pictures below) was introduced in 2005. The new I/O Card uses a different communication protocol that will require new firmware to be installed in order for C1900's to communicate with it.

    PLEASE NOTE: The new firmware IS backwards compatible to the original I/O Card.


Older DIP Version I/O Card (C1900-0255):

Newer SMT Version I/O Card (C1900-0405):



If Firmware (IC23) is C1900-2101 ISS. 6 or earlier: You will need to upgrade to ISS. 7 or later. This is a field upgradeable procedure.



If Firmware (IC23) is C1900-2001 Any Issue: You will need to upgrade to C1900-2101 ISS. 7 or later. PLEASE NOTE: This may not be a field upgradeable procedure. To verify, you will need to check the speed at which the processor operates* (When C1900 were first introduced, the processor ran at 8MHz. This was later upgraded to 12Mhz. C1900-2001 Firmware had an option to set system speed. C1900-2101 is an EXCLUSIVE 12MHz chip.).

If you have a 12MHz processor, then the upgrade is field upgradable. If you have a 8MHz processor, please contact us and we will gladly convert it for you.

* The only sure way to verify system speed is to find the Crystal located next to the processor chip (XTAL2). The speed should be stamped on the side of the crystal. A Secondary method is to examine the part number of the processor (IC20) itself. If the part number ends in a 3 (MC68HC11D0CFN3), you more than likely have a 12MHz processor board.



How to upgrade C1900 Firmware:

Detailed Steps:


Remove Firmware (IC23), which is inserted in a 32-pin socket, from Processor board using either an IC puller (preferred), or a small screwdriver.  Be VERY careful not to touch the pins while removing, there is a capacitive charge that could short the board and damage the components.


Install new Firmware. Use caution when aligning not to bend or seat pins incorrectly.


Apply power to the unit. It is generally recommended to always do a factory standard upload after changing Firmware. You can get that procedure by clicking here.




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