New board JTAG error

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Hello every one,
                                   We have designed a board which
contains an ALTERA fpga and an EPROM(EPC2LC20).The design is done with
respect to some existing reference schematics.We have populated our
PCB so as to get the power to all the components and then we have
placed the  components making up the JTAG circuitary along with the
FPGA and EPROM.
                                  ,Altera's Byte blaster is being used
which is working fine. have checked all the circuitary which seems to
be alright but we keep getting the error"Unable to access the JTAG
chain".We have also tried the steps in the ALTERAs trouble shooters.
                                 Do we need to  proceed in a different
way while programming the chip/EPROM for the first time.And also what
is the passive serial mode in the Quartus tool for programming. Any
help would be highly appreciated.Thanks in advance.


Re: New board JTAG error
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Hello.. Satish?
                                    Please tell us what voltage your
FPGA's JTAG port is configured for.  Does your Byte Blaster have a
voltage range that's compatible with this chain?  The programmers have
been around in various forms for ages; if you're using an old
programmer, it may not be compatible (or may require special tweaks) to
interface properly.
                                    ,As far as programming using the
passive serial mode, have you read up on the (most probably) abundant
literature that focuses explicitly on configuration?  Because *all*
designs need to be configured, *all* the engineers need to understand
how to work in their mode.
                                   Do you have more than just the Altera
FPGA and EPROM on board?  Do you have a processor that can store the
configuration file and bit-bang some FPGA pins through the processor
GPIO?  If so, you have all the access you need for the passive serial
configuration; it's just a matter of reading up on how to do what when.

Good luck,
- John_H

Re: New board JTAG error
Thank you John.
                                  The voltages are configured for
3.3V.All the circuitry  seems to be O.k. The download cable does
support the FLEX device.With a similar board we are able to detect the
devices through this cable.


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