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Altera_Forum
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13 years ago

Cyclone IV E JTAG issues - VCCA voltage level

Hi all, I have a custom board with Cyclone IV E (EP4CE115-F484). I am trying to access it via JTAG from Quartus, but keep receiving the "Error: Can't access JTAG chain". I check the Quar...
Altera_Forum's avatar
Altera_Forum
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13 years ago

Yeah, thanks, the thing is, the TDO signal is JUST A TRACK to the header, no pullup, pull downs, nothing. So my suspicion is that possible the pin driver got damaged by the USB blaster. It could be that the USB blaster is damaged, putting to high a load on the TDO pin, thus damaging it.

BUT, whilst I can program, I will try to sort out the configuration from the EPCS through the TXB0304. I can tell you I did not spend a lot of time on selecting this device and will probably pay the price now. The datasheet shows it can handle 150Mbs, so I figured it would be ok for the config data.