Answers Database

BOUNDARY SCAN/JTAG: XC4000 /INIT pin state during boundary scan


Record #143

Problem Title:
BOUNDARY SCAN/JTAG: XC4000 /INIT pin state during boundary scan


Problem Description:
Keywords: xc4000, init, configure, low

Urgency: Standard

General Description:

The state of the /INIT pin on a XC4000 family device during
configuration using Boundary Scan.


Solution 1:

In order to configure the XC4000 family devices using boundary
scan, it is important that the INIT pin be held low till after
the CONFIGURE instruction has become current.

Momentary glitches on the INIT pin may cause the device to be
thrown out of boundary scan mode, or to give nonsensical scan
outputs.




End of Record #143