Hi,
I am have a external processor attached to my custom board with DA14585. The external chip's IO pin is connected to PORT0, PIN2. I am configuring this pin as Input without pullup. The external processor has the pin pulled high most of the time. When the data is ready, it pulls down the pin. But I am not able to read a low when i read using GPIO_GetPinStatus(GPIO_PORT_0,GPIO_PIN_2). When i checked it on an oscilloscope, the low signal level is at 0.8V and high signal is at 3.3V in that pin. Why the offset of 0.8V?. What am i doing wrong here?.
For a test, I changed the pin to GPIO_PORT1, PIN0 and it works well and I am able to read the stage correctly. Why the offset on PORT0 pin?.
Regards,
Mark
Device:
Hi Mark,
Can you please share more inputs for this? Is the P0_2 used for any other purpose in your setup? For example, P0_2 is used as SPI_MISO (STEP B) when the DA14585 boots from SPI Flash and acts as slave device. Does the DA14585 act as master or slave device? Would it be possible to share the pin configurations?
Thanks, PM_Dialog
Pi PM_Dialog,
I am using a custom board for my application. I am communicating with the external processor via three GPIO pins of which 2 are from PORT0 and 1 pin is from PORT1. The PORT1 pin is working fine. The 0.8V offset in low condition occurs only on PORT0 pins.
Regards,
Mark
Hi Mark,
Could you share your shematic of your 585 custom board.
In addition,regards the operation of the PINs,could you post some code snippets about it.
Br， Yibin