So basically you do agree with me that I have to
disable/re-enable the SPI after every byte?
Regards,
Thomas
--- "Thomas C. Sefranek" <tcs@CMCORP.COM> wrote:
> Microchip did the WORST job implementing SPI in the
> PICs.
> Slave select is NOT,... it is slave sync, and TX
> enable.
>
> There are modes within the 4 possible that do not
> work with
> continuous data.  There are modes that do not
> interrupt after
> the first byte unless you disable the SPI and re
> enable it every byte.
>
> There are modes that with slave select DISABLED! the
> SPI continued on
> answering the clock/data stream.
> I ended up having to add an external PAL to qualify
> the SPI clock
> to get SPI to work correctly.
>
>   *
>   |  __O    Thomas C. Sefranek   WA1RHP@ARRL.NET
>   |_-\<,_   Amateur Radio Operator: WA1RHP
>   (*)/ (*)  Bicycle mobile on 145.41, PL 74.4
>
> http://hamradio.cmcorp.com/inventory/Inventory.html
> http://www.harvardrepeater.org
>
> > -----Original Message-----
> > From: pic microcontroller discussion list
> > [mailto:PICLIST@MITVMA.MIT.EDU]On Behalf Of Thomas
> > Sent: Friday, March 26, 2004 10:34 PM
> > To: PICLIST@MITVMA.MIT.EDU
> > Subject: [PIC:] SPI Slave - Need to toggle /SS
> signal for every byte?
> >
> >
> > Hi,
> > If a Master PIC wants to send multiple bytes of
> data
> > to a Slave PIC (with SS enabled) using SPI, does
> it
> > have to pull the SS line high at the end of every
> > byte?  The slave receives data perfectly with
> this:
> > - SS low
> >   - Send data
> >   - Delay 10ms
> > - SS high
> > - SS low
> >   - Send data
> >   - Delay 10ms
> > - SS high
> >
> > However, The slave doesn't receive data properly
> with
> > this:
> > - SS low
> >   - Send data
> >   - Delay 10ms
> >   - Send data
> >   - Delay 10ms
> > - SS high
> >
> > Both the slave and the master are F877 @ 20Mhz.
> Did I
> > do something wrong?
> > Regards,
> > Thomas
> >
> > --
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> >
>
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