Burst reading FIFO with SPI

[dansha]

Hi there,

I need help using the LINX interface with RPi, trying to control a device (MAX30009) through SPI. I manage alright, but I am not sure how to burst read the FIFO. Any help would be greatly appreciated.

danny.

[jorgemondadori]

Hey dansha, 

took a look at the data sheet and pages 50 to 52 describe the protocol very well.

unfortunetly i cannot test, don have this IC here. but if i would try something, i would go by using a bit bangging approach, practically creating the protocol in LabVIEW. 

by the way, i recently uploaded a video about a SPI not working and had to use this bit bangging approach. The video is in Portugues, but you may follow what i did. and feel free to ask for more information here or on the comment section.

https://youtu.be/d2maC57lmXs

[dansha]

Hi Jorge, many thanks.

I tried your approach, rather interesting, but I am not sure if I can combine it with the standard SPI vi's, as the digital I/O vi's  seem to object to the use of pins 19, 21 ,23 which are the ones the RPi is reserving for SPI. Is the bit-banging method mutually exclusive to the standard SPI?

danny.

[jorgemondadori]

hey, i really dont know. probably SPI pins are reserved, so no, you cant use them. But if proposed approach helps you to achieve your goal, why not forget about SPI and just use this approach?

i used other pins for my bit bangging (11 13 and 15)

[dansha]

I suppose I can, just a bit more work. I wish someone would write this into LINX.

Thanks!