Swdio/swclk shared with normal GPIO

[silvergaucho]

Hei there! First of all thanks for all the great work here!

My question is:

In my application, the final device will have 4 pogo pins. Two of them are for power, the other two for signal. These signal pins coul be connected at the same time to swdio/swclk for programming and to two normal gpio used later for I2C?

Thanks to everybody

[RK]

The question is a bit hard to understand. I think you're asking whether you can connect two of your pogo pins both to the SWDIO/SWDCLK and also to two other pins on the device which are GPIOs at the same time and use them to first program the device, and later as IO.

No. Not without some kind of external circuitry you couldn't. The SWDIO pin is also nRESET so as soon as you blipped that low the chip would reset. The SWDCLK pin is what turns on the debug interface so as soon as that changes from low to high, you'd enter debug mode and the signals on your I2C would also interpret as debug commands.

[silvergaucho]

Thanks RK, you got the point! OK, I have now to find out a better solution. Thanks again