Hi Guy, is the source available for your SPI0 slave implementation on the
BBB? I am running BBB Master - BBB Slave and am finding no examples for
running the AM3359 in slave mode.
Thanks
On Thursday, June 5, 2014 3:02:30 PM UTC-7, Guy Grotke wrote:
Yes, I was talking about trying to do
Thanks Guy Grotke... could you help me out with resources I can use to
implement bit-banging... Also I have not worked on PRU's, will try
reading up and get back to you... btw I dont think the MUXing will work,
because I want all data to be collected simultaneously (at run-time)...
On
Hey William...
I do know that the Chip Select line can be used to toggle between different
SPI units... But I need data to be collected simultaneously from multiple
sensors... As of now I have 32 sensors - I have clubbed them into groups of
4 and so I have 8 sets of SPI units that I want to
Sounds like fun. Good luck :)
On Wed, Jun 4, 2014 at 2:17 PM, swapnes...@gmail.com wrote:
Hey William...
I do know that the Chip Select line can be used to toggle between
different SPI units... But I need data to be collected simultaneously from
multiple sensors... As of now I have 32
but you can't run the clock much faster than 1 KHz using a user-space
program under Linux.
Not true at all! You can get over 3MHz just fine with mmap to the gpio
registers. If you try to open and close a file each gpio toggle, like the
insanely inefficient sysfs interface, then yeah...you'll
Yes, I was talking about trying to do hard real-time data collection in
a user-space program. If you look at the maximum interrupt latencies
from other stuff running on the system, then you see just why PRUs are
necessary to always meet your deadlines. Most of the time, a user-space
program
I am trying to run multiple SPI modules (more than the two available on the
BBB) to try and read data from a bunch of accelerometers (LSM303D).
I was therefore wondering if it would be possible to implement the SPI
module using code (preferably C/C++) on the abundant GPIO pins. I have been
It sounds as though you need to read more concerning what SPI actually *is*.
*Devices communicate in master/slave mode where the master device initiates
the data frame. Multiple slave devices are allowed with individual slave
select lines. Sometimes SPI is called a four-wire serial bus,
You could bit-bang SPI Master using some GPIO pins, but you can't run
the clock much faster than 1 KHz using a user-space program under
Linux. With a custom driver, you could run faster but it would still be
limited by the interrupt latency caused by other ISRs. You could do it
using a PRU
