I am facing an issue with BF533 and AMS interface, the issue is not about interface not working, but about my understanding.. I wish you guys can help me get my doubts cleared
This is how hardware is placed out - a 45 ns SRAM is connected to AMS0, a Flash memory is connected to AMS1 (comes into picture only during start up) and another ASIC is interfaced as external memory on AMS3
AMS0/AMS1 do not use ARDY and they are configured (EBIU_AMBCTL0 ) with something like 4 read / write cycles, 1 setup,1 memory transition ND ARDY disabled
where as AMS3 (ASIC) is configured with 3 read / write cycles 1 hold, 1 setup,1 memory transition time and ARDY enabled.
As per ASIC specification XRD pulse width should be 115ns and XWR pulse width 83ns, BF533 is running at 98 Mhz.
Though XRD/XWR pulse width are not matched ARDY must be taking care of it.
is my assumption is correct?
ASIC- BF interface is working fine in most of the cases but on certain boards I am facing some memory corruption
Second, is this memory corruption (1-2 bytes at same location) can be timing related?
(the memory corruption is observed only in 1-2 boards out of 10, in total I have almost 12 such faulty devices with me)
While working on timing I found if I set AMS3 (EBIU_AMBCTL1) with 0xFF55, i.e. 15 read / write cycles few of these faulty units do work properly.
But I am worried if I keep AMS3 with 15 read / write cycles, will it affect the SRAM performance?
I am not sure if i was able to explain my situation completely, please let me know if any more inputs are required.
Any help would be really appreciated.