MicroPython: control shift register (74HC595) via SPI
Posted: Sun May 14, 2017 3:45 amHi guys,
I've an issue with my current micropython project on my ESP8266. I've a 10x10 LED matrix which i would like to control via 4 shift registers.
In general 3 pins are required for the controlling DATA, LATCH and CLOCK. After some hours of internet searching the most promising solution was the usage of SPI, where also found some useful instructions for the pyboard platform:
viewtopic.php?t=1219
I tried to replace the pyboard specific librarys with the general machine module for the ESP8266 to get access to the SPI class. It worked fine till a specific point but the main issue at the moment is that it was not capable provide a binary signal at the DATA pin.
To be honest i'm a little bit confused about the write methods in the machine.SPI class. The docu says the return value is None. So in general what is the purpose of a write method with a return value of None
(sry for the maybe silly question)
Is there maybe another solution to get a binary signal out of the data pin? I'm not sure anymore if the usage of SPI is the best way to manage the controlling. Do you have some other examples or tutorials to get deeper into the topic?
Thank you for your kind response in advance,
BR charlzo
I've an issue with my current micropython project on my ESP8266. I've a 10x10 LED matrix which i would like to control via 4 shift registers.
In general 3 pins are required for the controlling DATA, LATCH and CLOCK. After some hours of internet searching the most promising solution was the usage of SPI, where also found some useful instructions for the pyboard platform:
viewtopic.php?t=1219I tried to replace the pyboard specific librarys with the general machine module for the ESP8266 to get access to the SPI class. It worked fine till a specific point but the main issue at the moment is that it was not capable provide a binary signal at the DATA pin.
To be honest i'm a little bit confused about the write methods in the machine.SPI class. The docu says the return value is None. So in general what is the purpose of a write method with a return value of None
(sry for the maybe silly question)Is there maybe another solution to get a binary signal out of the data pin? I'm not sure anymore if the usage of SPI is the best way to manage the controlling. Do you have some other examples or tutorials to get deeper into the topic?
Thank you for your kind response in advance,
BR charlzo