Answers Database
FPGA Configuration: INIT goes low unrelated to frame error.
Record #2645
Product Family: Hardware
Product Line: 5200
Product Part: 5200
Problem Title:
FPGA Configuration: INIT goes low unrelated to frame error.
Problem Description:
Urgency: Standard
General Description:
A configuration fails with the INIT pin driving low again. INIT goes low in the middle
of a frame, even before the first CCLK edge was sent (no CRC related error). This is
the result of Boundary Scan getting activated.
Solution 1:
During the time when INIT is low, the 4000 and 5200 fpgas are
sensible on their bounary scan pins. Activity on this pins
can cause the described behavior.
There are some ways to prevent this to happen:
1. do not use TCK as user IO
2. use TCK as output only, no other driver can toggle this pin.
3. set TMS = High during configuration. That keeps the
boundary scan state machine in the TEST-LOGIC-RESET state.
End of Record #2645 - Last Modified: 03/01/99 16:09 |
