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Trouble sharing SPI pins with SD Card and another device using fsrw26
I have been using fsrw26 for many years without issue. I often use multiple instance of fsrw26 to work with multiple files without issue.
I am currently working with a hardware design that shares SPI pins with another device. My goal is to read data from an SD card and, using the same SPI pins, to transmit the data to another device. The SD card and other device share CLK, MISO, MOSI pins, and each have their own dedicated CS pins. The pins have pull up resistors.
It appears to me that when fsrw26 mounts the SD card, opens a file and reads a byte, fsrw26 does not release the SD Card CS pin; the pin remains actively driven low.
There are PASM lines in safe_SPI that read:
' if you are using pull-up resistors, and need all
' lines tristated, then uncomment the following line.
' for Cluso99
' mov dira,#0
Uncommenting this line does not resolve the issue.
Is there a magic bullet that you can share to accomplish my goal?
Edit: Uploaded a schematic diagram