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How do I configure USB 8451 using SPI and 4 Chips for parallel acquisition?

<I have re-posted this query due to a lack of response on the DIO channel>
Hello,

I am about to use Melexis 90316 IC's: 4 of them. I am communicating using the SPI framework with the USB 8451. Figure 17.4.2 of the datasheet I have attached essentially shows how I would connect the chips. Here's the problem: I am looking to acquire all the data at the same time, but the 8451 only has one MOSI and one MISO port. Is there a way to setup the DIO channels on the other side of the device to acquire the MISO data continuously and in parallel from all 4 chips? Additionally: I have just begun to familiarize myself with the C++ API: do I have to run everything as a script to make things go faster? How does one do continuous streaming of input data without constantly having to query each IC?

Thanks for your help!
Nathan
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Hey Nathan,

Unfortunately the 8451 can only communicate with one device on the MOSI/MISO at a time.  Therefore for this application you will need 4 8451's to acquire MISO data continuously and in parallel from all 4 chips.

Best regards,

Jason W
Applications Engineering
National Instruments
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Hi,

 

Do you know how to have the MOSI line stay low until a data bit drives it high?  Right now, mine stays high and then goes low.

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