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Altera_Forum
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16 years ago

communication between Cyclone III and MAX II in Cyclone III development kit

Hello, We are working on Cyclone III 120 dev. kit. I could not figure it out from the reference manual about communication facility between MAXII and Cyclone III devices. my task is to im...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
16 years ago

The support response clarifies, that user USB communication must be regarded as an unsupported feature with the CIII 12ß Dev Kit. A hardware options is provided, but nothing more.

As a first comment, I don't understand this support statement:

--- Quote Start ---

FTDI device is used by on-board USB Blaster. The customer can’t use this device.

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In my opinion, you can use the FTDI device for user communication with reprogrammed MAX II. I would always prefer it for low and medium throughput, because of an easy programming interface.

If you don't mind, that the FTDI device enumerates as USB Blaster, you can keep the EEPROM settings and access the device through FTDI DLLs anyway, otherwise you can reprogram the EEPROM with the FTDI Mprog tool.

As I mentioned previously, the shared bus is an option to connect the USB_PHY (through MAX II) to the FPGA. Also USB_PHY_FD[7..0] provide an 8-bit data connection to both USB devices. But to utilize the Cypress device at USB high speed, a 16 bit data interface is required, I think.