I've got a PSP problem on an 18c452. Here, my external device (a host
PC) writes to the
 PSP seem to work fine. However, On occasion it appears the OBF bit is
being cleared when it
 should not.
        At one point in my code, the host sends a command to reset the
HostReadPointer in the PIC.
 When I reset this pointer (now making the data in latd invalid), I write
new data to latd.
 Watching a trace using MPLAB ICE, I can see that between the time I
write the new data to
 latd and the time my code discovers that OBF is low, there -RD has not
gone low (I'm
 watching it using an EXT input on the ICE). So, why, on occasion, is my
code finding OBF low
 (and writing new data to latd, even though the last data has not been
picked up by the
 host). It SEEMS that no matter what happened before, a write to latd
should force OBF high.
         If I could, I'd force OBF high when I reset my pointer, but OBF is read
only.
 What's fun is that this only happens now and then. It causes data I'm
pulling out of the PIC
 to be off by one byte.
        Any ideas appreciated!

 Harold


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