Hello,
we are using the ISP 1582 from Philis in our product. To be precise: We want to use it. But we have difficulties to let our firmware run.
Our problem looks like this: We are transmitting USB packets with sizes of between 20 and 100 bytes to our PC. We do not use the DMA interface, have 16 bit access and double buffering is enabled. Currently we are using only one endpoint for data transfer. Everything works fine until suddenly (after few seconds) the first two to four words of the transfer=packet (because of a packetsize of less than 512 bytes) seem to be the last two words of the predecessing transfer.
Example
It should be this way: Transfer(n) : 0123 4567 89AB CDEF 0123 Transfer(n+1): 0011 2233 4455 6677 8899
But this is received by the PC: Transfer(n) : 0123 4567 89AB CDEF 0123 ^^^^ ^^^^ Transfer(n+1): CDEF 0123 4455 6677 8899 ^^^^ ^^^^ While we are copying the transfer to the fifo we disabled every interrupt in our processor in order not to change the endpoint while copying.
Does anybody know this or a similar problem? What is your experience with the ISP1581 / ISP1582?
Sinx