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AR# 1385

xchecker - "Error 264 : Done signal did not go high" or "Error 265 : Init still low"


Keywords: xchecker, done, init

Urgency: Standard

General Description:
XCHECKER used on PC returns error message:

"Error 264 : Done signal did not go high or
Error 265 : Init still low"



One possible reason could be a Dos extender issue. In this case, try "XCK88.EXE" instead of "XCHECKER.EXE."

"XCK88.EXE" is compiled with 16-bit integer, and "XCHECKER.EXE" is compiled with Metaware386.

For small and standalone environments, XCK88 was prefered because it takes much less memory.

"XCK88.EXE" is available on the Xact Step 5.2 or 5.2.1 CDs, under the directory "/XACT."


The possible issue with error 264/265 is that the design has not been configured properly.

1. Verify that you compiled your design for the correct part type and package.

2. Make sure that you set the target FPGA for the serial slave mode. The xchecker only downloads in Slave Serial. The mode pins <M0 M1 M2> on the FPGA should be set to <111>.

3. Check all connections for slave serial. Remember that connections to the FPGA differ slightly across the different families.

4. Check the bitstream options in makebits or BitGen and verify that you selected a pull-up for the DONE pin.

5. Check for noisy signals that may corrup the data or CCLK going to the target FPGA.

6. For information on how to properly connect the xchecker to the target FPGA, see the Hardware & Peripherals User Guide, "XChecker Cable and Logic Probe" section, available at:

7. For further debugging, see (Xilinx XAPP090) - FPGA Configuration Guidelines.
AR# 1385
Date 09/30/2005
Status Archive
Type ??????