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Unable to scan device chain

I'm soldering up my first FPGA design and I'm getting discouraged.

I'm using an Altera Cycline with an EPCS1 serial configuration device. I've soldered up the passives and the power supply but the only active part I've put on the board is the configuration PROM.

I've connected my ByteBlaster to my board, and it doesn't see the PROM device. I get the error "Unable to scan device chain. Can't scan JTAG chain." Quartus will, however, see the Cyclone device on another (also not-working) board of mine.

I've checked and double-checked the connections per Figure 4-2 of the Serial Configuration Devices datasheet, and the continuity tester says it all checks out. I've tried the PROM soldered in both ways, but no success.

Are there any magical troubleshooting steps out there I don't know of? It's quite discouraging that I've spent this money to have custom boards made, paid for parts, etc. and find that I can't program the PROM.

Thanks in advance for any tips.

-Matt

Reply to
Nevo
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That might be the clue. I don't know the pinout of the PROM device, but they often use power and ground on diagonal pins. If you put it in backwards the first time, it is ruined and turning it around will not help. Figure out which way is right and put a new one on the board.

Yes, there are lots of magical steps. But we can't share them or we are banned from the coven.

Reply to
rickman

A JTAG chain is usually a "chain" with outputs from one chip feeding inputs of the other. Is your ByteBlaster indeed connected directly to the TDI and TDO pins? If you have the FPGA as part of that chain yet not installed, there's a link missing.

Are you aware the board has to be fully powered up to have the JTAG work? The ByteBlaster alone will not make the device (your PROM) come up. It may sound like a silly question but all I know is this is your first FPGA design.

- John_H

Reply to
John_H

Aha! I went to bed last night pretty discouraged, but found a ray of hope this morning.

It seems there's a power supply issue on my board. I don't think I'm going to be able to solve the programming issue until I solve the power supply issue.

Stay tuned... :)

Reply to
Nevo

There is no chain, just the PROM device. Yes, I am powering the board during the scan. (Thank you, though, for pointing that out!)

Reply to
Nevo

Matt

The EPCS should be programmed using the 'Active Serial Programming' mode, not JTAG.

André

Nevo wrote:

Reply to
Andre

Andre,

From within Quartus, I'm going to the Tools menu, selecting Programmer, then clicking on Auto Detect.

Is that not appropriate for the EPCS device? If not, then how do I program the device from within Quartus?

-Mat

Reply to
Nevo

Never mind. Found it.

Thank you for pointing that out. I wouldn't have figured that out on my own!

Reply to
Nevo

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