unable to use reset pin as gpio

[madblue]

Hi,

I am trying to use the p21 reset pin as gpio but it is not working as expected. it is showing a 3.3v even when i am trying to toggle the pin. I have removed the CONFIGURE GPIO PI AS RESET definition  from the makefile and the reset function is disabled. also tried disabling the reset configuration in systemnrf_52.c file.

nrfjprog --memrd 0x10001200 and 1204 gives 0xffffffff.

what else should i do other than disabling the CONFIGUREGPIOPIN AS RESETdefinition ?

I am using nrf52832(bc832 module) with sdk14.00, softdevice s132

[FormerMember]

The readout from UICR shows that no pin is set as reset pin.

How do you configure the gpio? Do you use the GPIO HAL?

[madblue]

Hi kristin,

when i removed the softdevice the gpio started toggling. seems the s132 was causing some issues. Does it work with softdevice?

but now there is a new issue, when i am trying to use this pin for twi its not working properly.ie.. i have connected it to sda line, as it was not working i have used a logic analyzer to view the communication and found that regardless of the what value i am trying to send, it only gives zero.

suppose if i try to write 0x57 to the slave, the values going out is only 0x00. clock and start conditions are going well. There is a 10k pull up connected to the sda line which i have removed as part of debug. it seems some kind of logic level issue is there with the pin.

fyi, the twi slave is working fine with a different gpio pin(02).

[hmolesworth]

In case you are using a development kit similar to the nRF52 dev kit the nRESET pin P0.21 is hardwired to an output on the SAM3 Segger interface via a solder bridge which may be cut. It's SB27 which may be causing the issue you see.

[madblue]

Thank you hmolesworth for the support.

we are using a custom board based on bc832. there is nothing connected to the line otherthan  a pull up, which can be removed. the pin is directly conncted to the slave data line.

Have you ever tried to use this pin as any communication line like twi or spi. do you think its a bug in the design end or bc832 side.