Hello I m new to this
i have brought altera USB Blaster to program altera IC.
i have one usb blaster altera and some altera ics part no EPM7160SLI84-10N
when i select auto detect in Quartus II some IC detects but for some IC error comes like
"Unable to scan device chain.Can't find Jtag chain.Do u want to open the JTAG chain Debugger to troubleshoot the JTAG chain"
The message is pretty clear. It means JTAG chain not working.
Possible reason, device not powered, not properly connected or defective. In case of MAX7000S series, the JTAG interface might have been disabled. If so, you need a parallel programmer to reprogram the device.
If the device not powered, not properly connected or defective it show for all ICs. i have IC part no EPM7160SLI84-10N quanity 10 out of which 4 are detecting and other 6 are not detceting. why this happens.
It detects some ICs. Are these detected ICs correct?
I´m asking because....Afaik they are detected by sending a known sequence of bits through the JTAG chain and the programmer (software) checks the output of the chain.
Each IC may have a different count of bits latency. Maybe all ICs are working properly but the programmer just interprets the reciving data wrongly.
The idea that it wrongly interpretes the latency of two ICs as one larger latency of a single IC.
Is it possible to "force" the device chain to the programmer instead of "self detect"?
New from an authorized distributor, or "new" parts from some internet site.
FYI, there are a lot of grey market parts out there, it's a lucrative buisness that caters to people's desire to get something for nothing.
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If you can force all 1's through the JTAG chain you can get a readout of all the IDCODES of the parts. Does the tool report the idcodes read from the parts?