Forum Discussion

Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
21 years ago

Nios-II SOPC UART delivers wrong bytes

We use the UART in our Nios-II design that comes with Quartus 5.0SP1 and Nios-II 5.0 We face the problem that sometimes the Uart reports wrong RX Bytes from correct RX streams. The serial str...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
21 years ago

We are finding the same or a similar problem. We have 2 devices, we program one to just transmit. Every four seconds we send a blast of data 0-255. If we enable Rx and listen to ourself on that device, we hear all 256 characters nice and clean. We then plug into a second device and enable it to Rx. We loose about one byte in 16. We have tried blocking, non-blocking, read only, read write, disabling the transmitter. We have tried open(), fopen(), we have used getc() and read(), and more.

These have no apparent affect on the input. The scope shows what looks like a clean pattern. Anyone with solutions would be GREATLY appreciated.

Regards,

Jeff Ballif