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Altera_Forum
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17 years ago

Cyclone 3 migration from EPCS64 to EPCS128

Hello all, In our design, we are using successfully the EP3C10 and EPCS64 configuration device (AS mode). We need to switch to the 128Mbit device (EPCS128); the FPGA fail to config in that case:...
Altera_Forum's avatar
Altera_Forum
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17 years ago

I understand, that the read ID instruction is executed first, before reading any data from the device. If so, the issue can't be related to the serial flash content and isn't controllable by Quartus anyway. It's a matter of Cyclone III silicone (configuration controller IP) only.

As you already found out, there's nothing specific to selected configuration device in configuration data, the different file types have basically identical content, except for a different header that is stripped of before programming.

What happens after the Read ID command failed? Does the configuration process start a new or is there any additional communication with AS device?

In addition to the said handbook references, I didn't find any hints in Altera knowledge base. So if EPCS128 is actually unsupported by Cyclone III, the bug seems to be yet unknown at Altera. If it's a silicone bug, I would expect that it isn't specific to a particular Cyclone III chip.