SPI bus conflict

[Mk]

Hi,
I need three PICs to communicate with each other via SPI bus. I setup one as a SPI Master and the other two as SPI Slaves.

The communication was fine with 1 Master and 1 Slave until I connect the second Slave to the SPI bus . I think the problem is related to the SDO signal of the two slaves. When the SPI Master wants to talk to the second Slave, because the SDI signal of the Master is held either high or low by the first Slave, the second slave cannot toggle the SDO pin (since they are tied together at the Master's SDI pin).

I tried to sum the two SDO signals of the two Slaves via 1K resistor, but the comm is still intermittent. Is there other anyway around this? Thanks!
Best regards,

[asmallri]

Sonds like you are asserting the chip select for both slaves at the same time. Only one slave should be active at a time.
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Regards, Andrew

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