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Altera_Forum
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10 years ago

Identify EPCS and EPCQ

Hi, We use remote programming. How to identify if the memory is EPCS or EPCQ ? They use different opcodes for identification, is there a way to identify if the memory is EPCQ or EPCS ? ...
Altera_Forum's avatar
Altera_Forum
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10 years ago

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I think that EPCS don't support (except 128) "Read device Identification" and EPCQ doesn't support "Read Silicon ID", am I correct ?

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Correct.

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What do they return if "Read silicon ID" is used for EPCQ and "Read device Identification" for EPCS ?

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The DATA (EPCS) or DATA1 (EPCQ) signal is high-impedance when it's not driving. This will be the case when you issue an instruction they don't recognise. What you read back will depend on your design.

If you have a convenient pull-up (which is, probably, not likely to be the case) you'd get something predictable - 0xFF. However, even without you're unlikely to read back a valid device or silicone ID from a device that doesn't support the command.

So, you should be able to distinguish these parts using these two commands.

Happy New Year,

Alex