SWD Programming with 2 devices on the bus

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cross mob
Anonymous
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I'm looking into programming my boards in a production environment. I've looked into OpenOCD and am working with those folks on expanding the current coverage to include more devices. As a backup plan I read the app note about using another PSoC as a programmer in what's called HSSP. 

   

I'm designing a board that will have a PSoC 5LP on board connected to a FM24V10 FRAM part. The SWD pins are connected to a set of pogo pins which will probe my PRoC BLE module board (CYBLE-222005-00). Those pins are also brought out to a header which will connect to the board running OpenOCD.

   

If I just use the PSoC 5LP and HSSP programming I won't have issues (at least in theory). But if I want to use the board running OpenOCD it will see both the 5LP and the ProC BLE so how do you address different devices? I know that under the hood when you program by SWD it probes the chip using the DAP interface and reads the Silicon ID. That is then compared to the Silicon ID inside of the hex file you're using to program. What I haven't been able to find is what happens when there's more than 1 device on the SWD "bus"?

   

Thanks in advance for any helpful advice and information!

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Anonymous
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I think it may not be possible for two devices on the SWD Bus

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