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Can McBSP as spi master support only one slave device ?

Started by Jack September 13, 2003
I am using the McBSP as a spi master. Can it support only one slave
device or does it have the capability to support multiple slaves. I
know that dedicated spi master modules on other processors I have
worked with have support for more than one device through a few chip
selects.

Any help is appreciated,
Jack
On 13 Sep 2003 09:52:07 -0700, hemrin2000@yahoo.com (Jack) wrote:

>I am using the McBSP as a spi master. Can it support only one slave >device or does it have the capability to support multiple slaves. I >know that dedicated spi master modules on other processors I have >worked with have support for more than one device through a few chip >selects. > >Any help is appreciated,
Device selection (i.e. the chip selects you mention above) needs to be implemented using some other form of I/O. The McBSP only implements the serial protocol. Best Regards John McCabe To reply by email replace 'nospam' with 'assen'
Many typical SPI devices have active low chip selects. An easy thing
to do to use a two-input OR gate in front of each chip select pin. One
input is FSX, the other input comes from a spare DSP output pin. (You
need a spare output for each device on the SPI bus.) Pull that output
pin low to select a device and high to disable it.

David L. Rick
Hach Company
drick@hach.com


hemrin2000@yahoo.com (Jack) wrote in message news:<f313ed98.0309130852.644f2ed6@posting.google.com>...
> I am using the McBSP as a spi master. Can it support only one slave > device or does it have the capability to support multiple slaves. I > know that dedicated spi master modules on other processors I have > worked with have support for more than one device through a few chip > selects. > > Any help is appreciated, > Jack