Forum Discussion
4 Replies
- Altera_Forum
Honored Contributor
What does the documentation say?
- Altera_Forum
Honored Contributor
If it's similar to my Cyclone IV board, the MAX chip is part of the USB Blaster. At first glance it looks like it's mostly for voltage level conversion and maybe serial/parallel. It think there are some USB JTAG example circuits floating around on the internet, you might do some searches.
- Altera_Forum
Honored Contributor
You don't say which Cyclone III dev kit it is. However, as Galfonz states - it's probably part of the on-board USB-Blaster circuitry. If so, it shouldn't appear in the JTAG chain when you scan it.
However, if it does appear in the JTAG chain when you scan that it's more likely to be a 'system controller' and, as you suggest, may be used to select which image to boot the FPGA from. An example of this can be found on the cyclone iii ls fpga development kit (https://www.altera.com/products/boards_and_kits/dev-kits/altera/kit-cyc3-ls.html) and other, generally newer kits. Cheers, Alex - Altera_Forum
Honored Contributor
I'm not sure which Cyclone III dev kit you are referring to but the Cyclone III dev kit is not built with EPCS device. Typically there is a CFI flash device populate on the dev kit. The MAX II device on the dev kit work as the system controller on the board to perform the FPGA configuration, programming flash, clock and power monitoring and others. You can refer those information from the reference manual in the dev kit installation folder.