Hi,

I just found out that this is a better place to ask my question, it seams 
like there is also a beaglebone Google group, little confusing. So here my 
cross-post:

I'd like to connect 4 ADS8528[0] daisy-chained via SPI to a BBB. I want to 
test it in different iterations first I want to measure the 32 Analog input 
channels captured by the ADS8528s with 1kHz and at the end with 200kHz. 
Those ADS8528 using 4 SPI Channels in daisy-chain mode. So I did some 
calculations on the needed bandwidth:

for 1Khz:
12Bit * 32Channels * 4KHz = 384 Kbit/s 

On 4 SPI Channels that means:
12* 32*1Khz = 96 Kbit/s per SPI channel

for 200Khz:
12Bit * 32Channels * 200KHz = 76.8 Mbit/s = 9.6MByte/s

On 4 SPI Channels that means:
76.8Mb/s /4 = 19.2 Mbit/s per SPI channel

Now 2 things: 
 * Should/Can I use the built-in SPI of the BBB or do I have to implement 4 
channels SPI bus by hand (High datarates PRUSS I guess)?
 * Do you think the high datarates for the 200Khz are achievable?

Thanks,

/Julian

[0]: http://www.ti.com/product/ads8528

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