CY7C68013A Quick way to modify alt interface

[FrZa_2625781]

Hi,

in order to test something I use the CY7C68013A default settings with the built in alt interface 1.

Now I want to also use entpoint 2 as an input just as i do with endpoint 6.

I changed the address on the FIFOADDR pins and used a minimum firmware to just set the  EP2CFG and  EP2FIFOCFG to the according values (just the same values as EP6CFG and  EP6FIFOCFG).

Unfortunately this does not word.

The transfer requests return empty immediately. If I try the same with endpoint 8 (although not addressing endpoint 8 with the FIFOADDR pins), it seems at least to wait for data.

I suspect that the transfer request fails because endpoint 2 is listed as OUT in the interface descriptors even when I configured the above CFG bytes for IN.

I assume I would have to modify the interface descriptor.

How can I modify this quick and dirty?

Can this be done without having to load a full blown firmware into the chip?

[MallikaK_22 · Accepted solution]

Hi,

Apologies for the delay in response.

Yes, the issue seems to be because of the discrepancy between the descriptor file and endpoint configuration.

USB devices publish their endpoint to the host as part of an interface. So, the endpoint needs to be configured properly here. Please check dscr.a51 file in your source . This is the descriptor file that lists all the descriptors.

You should make the configuration compatible and then will have to load the firmware again. Since the descriptor file is being changed here, you will have to reload the firmware. 

Regards,

Mallika