Hello all I have designed a board with an XC3S400 and an XCF02S. I can configure both devices through the JTAG interface but master mode configuration doesn't work. I have a 3,3V compliant interface because I need 3,3V pins on all I/O banks.
- M0-M2 pins are grounded
- There is a 100 ohms resistor between Prog_b and /CF & pull-up
- CCLK runs OK (2,5V)
- D0 toggles between 1,5 & 3V !
- Done remains low I have all pull-ups on Done (470), Prog & Init (4,7k)
Any help is welcome
Well, that's what's wrong. D0 needs to toggle between 0 and 3.3V. Do you have a short between D0 and an adjacent pad? Cheers, Syms.
Symon a écrit:
Thought so too... I don't think it's an accidental short because the problem exists on the 2 boards we have. I'll check the design... Anyone got any idea why the output doesn't go down to 0V?
OK, there is a mistake in the schematics, I connected the output of the XCF02S to the Dout of the FPGA instead of the Din (luckily I can strap it) End of the story
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