Since I was concerned about the read doing another SPI cycle, I just
went right to the register using code like this:

  WriteSPI(ToExtSpi2.byte);             // Send the next byte
  while(!DataRdySPI());                 // Loop until data ready
  FromSpi2.byte=SSPBUF;                 // Read the next byte

        Seems to work. I've got it talking to a Maxim MAX3100.

Thanks for the help!

Harold


On Fri, 17 May 2002 08:23:52 +0100 "Alan B. Pearce" <A.B.Pearce@RL.AC.UK>
writes:
> >The problem is that it APPEARS (according to the documentation)
> >that BOTH WriteSPI and ReadSPI initiate an SPI bus cycle.
>
> I have not used SPI, but if I remember correctly from my perusal of
> the
> documentation, to read a character from the SPI, it does a dummy
> write. The
> SPI hardware then thinks it is writing a byte out to the bus, and so
> generates clocks which are actually reading in a byte. The apparent
> write is
> needed for the clock generation to occur.
>
> I have done this trick on other hardware I was involved with for
> this exact
> reason, it was the only way to make the clock generation circuit
> work
> correctly.
>
> --
> http://www.piclist.com hint: PICList Posts must start with ONE
> topic:
> [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]:
> ->Ads
>
>

FCC Rules Online at http://hallikainen.com/FccRules
Lighting control for theatre and television at http://www.dovesystems.com


________________________________________________________________
GET INTERNET ACCESS FROM JUNO!
Juno offers FREE or PREMIUM Internet access for less!
Join Juno today!  For your FREE software, visit:
http://dl.www.juno.com/get/web/.

--
http://www.piclist.com#nomail Going offline? Don't AutoReply us!
email listserv@mitvma.mit.edu with SET PICList DIGEST in the body