Hello,
I want to control relays with blynk app and i want to use esp8266-12e connected to like 4 74hc595 shift registers and they controling 24 relays.
But i am confused with the code is it possible? anyone have any links i can use?
please help me out with this.
thank you
No one will spoon-feed you with complete solution. Try searching the forum to see if anyone else have used the 74HC595 or spend some time with G**gle. There is code examples available!
In my experience, it’s often better to go for more of a modular design. The multi-relay boards that you get from China are prone to failures of individual relay channels, and I’ve seen reports on this forum of 8 or 16 channel relay boards arriving with multiple channels not working when new.
NodeMCU boards can also fail, but tend to be much more reliable.
Given the low cost of NodeMCU boards, I’d be tempted to go for multiple NodeMCUs driving multiple small relay boards (maybe 4 relays per board).
This also has the advantage of easier fault-finding, and allows you to locate the packs of relays in different physical locations if that helps with your wiring.
If you do want just one MCU doing the work then maybe it’s one of the few occasions when I’d say that an Arduino is the better board for the job.
Pete.
I am not seeing any clear hurdles.
See https://www.arduino.cc/en/tutorial/ShiftOut for an example on how to use the shifters. Get that working then add Blynk stuff.
Instead of driving LEDs, you would drive the input pins of the relays. Use relay boards that also take their own power input to drive the relay coils.