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AR# 24862

PROM-XCF00P - When playing an SVF file to the XCF00P device, pulsing PROG after file completion does not cause a configuration

Description

When playing an SVF, XSVF, or ACE file targeting a Platform Flash PROM device in a JTAG chain, the file completes successfully. At this point, pulsing PROG does not cause the PROM to load the FPGA.

Solution

This occurs because the PROM has been left in In-System Programing (ISP) mode. While the PROM is in ISP mode, only the JTAG pins are active.

There are three ways to get the device out of this state, as follows:

- Power-cycle the part.

- Return the JTAG Test Access Port (TAP) controller to TEST-LOGIC-RESET tap state. To do this, clock TCK five times while TMS is high. Returning to the TEST-LOGIC-RESET state removes the device from ISP mode. If you are using the iMPACT software to connect to the JTAG chain, you can do this manually by switching to JTAG "Debug Mode" and clicking the "TEST-LOGIC-RESET" button.

- Insert the CONLD command ("00F0") at the end of the SVF file. This command removes the device from the ISP mode.

Manual Edit

To manually add the CONLD command to the SVF file, you must add the following lines to the end of the SVF file. The TIR, HIR, TDR, HDR values change as per the devices in the chain, but the command is the same.

//Loading device with "conld" instruction.

SIR 16 TDI (00f0) ;

RUNTEST 50 TCK;

The original syntax at the end of the SVF file is similar to the following:

// Loading device with a 'ISC_PROGRAM' instruction.

SIR 16 TDI (00ea) ;

RUNTEST 60 TCK;

TIR 0 ;

HIR 0 ;

TDR 0 ;

HDR 0 ;

SIR 16 TDI (ffff) ;

SDR 1 TDI (00) SMASK (01) ;

The modified text should read:

// Loading device with a 'ISC_PROGRAM' instruction.

SIR 16 TDI (00ea) ;

RUNTEST 60 TCK;

TIR 0 ;

HIR 0 ;

TDR 0 ;

HDR 0 ;

//Loading device with "conld" instruction.

SIR 16 TDI (00f0) ;

RUNTEST 50 TCK

TIR 0 ;

HIR 0 ;

TDR 0 ;

HDR 0 ;

SIR 16 TDI (ffff) ;

SDR 1 TDI (00) SMASK (01) ;

Alternative Method to Manually Edit the SVF File

The CONLD ("00F0") command followed by the CONFIG ("00EE") command is automatically inserted into the SVF when the iMPACT "Load FPGA" option is selected in the PROM programming options window prior to programming. The CONFIG command causes the PROM to pulse the CF pin low for ~300 ns after programming is completed. If the PROM CF pin is tied to the FPGA PROGRAM pin, this causes the FPGA to clear its configuration memory and attempt reconfiguration if it is enabled.

This problem is fixed in the 9.2i design tools release, which is scheduled for June 2007.

AR# 24862
Date Created 09/04/2007
Last Updated 12/15/2012
Status Active
Type General Article