I also want to connect Some Simple Electronics.
So I designed A board with the purpose to give me:
- an isolated rs485 port.
2… an connector to attach a nrf24l01 module. - an connector to attach a i2c oled display.
Rs485 because, Well I just like it , and the nrf24l01 and oled because I’ve got a lot of them., besides that i think i can connect a lot of sensors ,relay’s etc.
The first Problem I Saw was that the gpio connector Run mostly on 3v en most of the chips i use use 3v3 or 5v. So some level shifting was in order.
I used a:
TXS0108 for the uart and normal io pins,
SN74AVC4T774 for the spi bus,
PCA9306 for the i2c bus
To these i connected :
ADM2587E , to give me a isolated rs485 port.
LM75b, i2c temperature sensor. To se if stuf is burning.
And for the nrf… and oled a couple of connectors
Circuit and bom
This link will work for one week i think,sorry.
Questions:
-Do you see Any problems with this circuit or Do You Still Think My Rock pi 4 will blow-up when i use it.and and Why .
- the ADM2587E is powered by 5v but the uart is shifted to 3v3, will this give problems, should i power it with 3v3(witch is possible). But then i got to buy some max3485 ic to conect to itand i already got some max485 ic
I hope to hear from you all.
Greetings bert