Hi everybody,

I'm getting a strange error with CY7C68013A.

An image sensor is filling the endpoint FIFOs in AutoIN mode and data is sent through an Isochronous pipe. If I send 1pkt/uFrame, data are correctly received by the host, if I send 2 or 3 iso pkts/uFrame, I get an error from the host controller (E0000B00:Iso Request Failed and every packet has status E0000011: XACT error).

FIFO is configured with AUTOIN and ZEROLENIN.

Here is the code:

             case Alt3_IsocIN:
                // Only using endpoint 2, zero the valid bit on all others
                EP2CFG = 0xD8;  // EP2 is DIR=IN, TYPE=ISOC, SIZE=1024, BUF=4x
                SYNCDELAY;

                EP2FIFOCFG = 0x0d;
                SYNCDELAY;
                
                EP1OUTCFG = EP1INCFG = EP4CFG = EP6CFG = EP8CFG = 0x00;
                SYNCDELAY;
    
                // Clear out any committed packets
                FIFORESET = 0x80;
                SYNCDELAY;
                FIFORESET = 0x02;
                SYNCDELAY;
                FIFORESET = 0x00;
                SYNCDELAY;
    
                // This register sets the number of Isoc packets to send per
                // uFrame.  This register is only valid in high speed.
                EP2ISOINPKTS = 0x03; // with EP2ISOINPKTS = 0x01 WORKS!!!

break;

and the descriptor:

;; Isoc OUT Endpoint Descriptor
      db   DSCR_ENDPNT_LEN   ;; Descriptor length
      db   DSCR_ENDPNT       ;; Descriptor type
      db   02H               ;; Endpoint 2 and direction OUT
      db   ET_ISO            ;; Endpoint type
      db   00H               ;; Maximun packet size (LSB)
      db   14H               ;; Max packect size (MSB) 10100b 3x1024 byte packets/uFrame
      db   01H               ;; Polling interval

I tried to manual flush the FIFO and in this case I correctly receive 3 pkts/uFrame!!!

Unfortunately I've no hardware protocol analyzer, so I cannot give deeper info about the isochronous transaction!

Thank you in advance!

I found an error in previous post! The endopint description is, actually:

;; Isoc IN Endpoint Descriptor
      db   DSCR_ENDPNT_LEN   ;; Descriptor length
      db   DSCR_ENDPNT       ;; Descriptor type
      db   82H               ;; Endpoint 2 and direction OUT
      db   ET_ISO            ;; Endpoint type
      db   00H               ;; Maximun packet size (LSB)
      db   14H               ;; Max packect size (MSB) 10100b 3x1024 byte packets/uFrame
      db   01H               ;; Polling interval

Here is another clue!!!

If I set endpoint polling time to 2 instead of 1 (250us instead of 125 us) transaction WORKS, even with 3 pkts/uframe! Unfortunately I need 3pkts/uframe with polling time of 125 us!!