Honored Contributor
Honored ContributorHi Max,
One way of getting your 256 bit wide data into/out of your peripheral is with 8 x 32 bit writes/reads. With a 4 bit wide address input to your slave you could latch writes to addresses 0 to 7 into slices of the 256-bit wide register, and have spare addresses for writing control flags/reading status flags. The Avalon signals you'd need to add to your logic would be read, readdata, write, writedata and address. The Avalon interface for this is quite simple. If write is asserted, latch writedata into the destination according to the address bits. If read is asserted, latch data from the relevant source onto readdata. From your C code, use the Altera IORD/IOWR macros to read and write your peripheral using the base address supplied by system.h. You would have to modify your existing hardware module to wait for a control bit to be written before executing the hash, and to set a status flag when the hash is complete. Your C code would then perform the custom function by writing 8 x 32 bit values to the data registers followed by a 'go' bit to the control register, and then polling the status register until the 'ready' bit is set. You can then read the result as 8 x 32-bit values. It would also be easy to use the 'ready' signal as an interrupt. I know this probably isn't as detailed a reply as you'd like, but I hope it at least gives you an idea of how to proceed, and if you have more specific questions feel free to ask. Cheers Sharkybaba
