Trying to set up an interface between TS-7800 and an SPI device, I
started looking at the SPI sample code from TS.
I was disappointed as there seems to be no hardware support for the
SPI "pseudo port". Instead the code streams one bit at a time out the
gpio port (including clock). That raises three serious questions:
1) Reliability: can the external device cope with data being streamed
as fast as a for loop?
2) Predictability: How fast are we sending data out of that port?
3) Efficiency: Do I want to my code to spend that kind of time (and
energy) using SPI?
That being said, I used the sample temperature sensor code and it
worked ok (uses the SPI sample code). The data sheet for the sensor
indicates that it can take up to 10Mb/s, my device can only do 1Mb/s
and I refuse to wait in between each bit sent or received though
SPI!!!
This cries for usage of the FPGA to buffer data and control the CLK
signal. I wonder why TS did not implement it!
------------------------------------
Yahoo! Groups Links
<*> To visit your group on the web, go to:
http://groups.yahoo.com/group/ts-7000/
<*> Your email settings:
Individual Email | Traditional
<*> To change settings online go to:
http://groups.yahoo.com/group/ts-7000/join
(Yahoo! ID required)
<*> To change settings via email:
<*> To unsubscribe from this group, send an email to:
<*> Your use of Yahoo! Groups is subject to:
http://docs.yahoo.com/info/terms/
|