ESP8266 Community Forum

- Wed Jan 17, 2018 12:41 am #73206

Interesting.

What makes you think digitalRead(MISO) isn’t working?

Since the MISO behavior of the chip is to indicate the clock is stable after reset, can you just skip checking it?

I can simply setup SPI and run digitalRead(MISO) with that pin pulled up and read 0. It's a simple test.

Unfortunately, the MISO state can be programmed to output various events when chip select is not pulled low for an SPI transaction. It's a dual use pin. I'm sure this is not the only device out there that has such a feature and I would think being able to read the MISO state with a digitalRead command will be useful. Who writes this code? IGRR?

- Wed Jan 17, 2018 2:29 pm #73229 What device is this? I’d like to read the data sheet.

- Wed Jan 17, 2018 2:58 pm #73232

What device is this? I’d like to read the data sheet.

As an example:
http://www.ti.com/product/CC110L/datash ... WRS1094452 Sec 3.2
http://www.ti.com/product/CC110L/datash ... WRS1099190 Sec 5.25

Other Chipcon/TI transceivers....

Whole slew of ADCs where SO is shared with a data ready indicator, e.g. http://www.ti.com/lit/ds/sbas457e/sbas457e.pdf

I suppose it's a quick way to check device status without initiating SPI traffic and potentially creating unnecessary noise to analog/sensitive sections of radio receivers and data converters.

- Wed Jan 17, 2018 10:38 pm #73245 Is your interest for a specific application, or are you trying to create something which implements all functionality of the chip?