Use MKR485 shield with Arduino UNO board

Hello everyone,

I bought an arduino uno board recently and I got an MKR485 shield.
I need some help, to use them together, as it is not an MKR board.

Thank you.

Return the board and buy one that will fit the UNO you have! Otherwise you will have to manually add jumper wires & level shifters.

As @missdrew says, the 2 boards are not compatible - well not in size anyway. I had a look at the schematic for the MKR485 and I think you should be ok with some jumper wires to your UNO. The MAX3157 runs at +5V. The +3V3 seems to be only used to provide a pull-up for RE via R7, so you could probably feed +5V in on the +3V3 pin as well.

Use AltSoftSerial from PJRC to provide serial comms to it using pins 14/TX and 13/RX on the MKR485 and control the direction with A5 & A6 on the MKR485.

The received data coming out of the MAX3157 RO pin goes though a potential divider to drop the 5V logic level down to +3V3 but I think your UNO will still handle that, given that most of the SD card readers also present +3V3 level signals back to an UNO and it works ok.

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I have a lot of jumper wires, it is okay for me; my original plan was something like this.

Could you please help me, how should I wire it to make it work?

@paladam1 - pretty much as I described in #3.

UNO GND β†’ MKR485 GND
UNO +5V β†’ MKR485 5V & VCC

If you use AltSoftSerial, then you need to connect as follows:
UNO 9 (Tx) β†’ MKR485 14
UNO 8 (Rx) β†’ MKR485 13

You choose which pin(s) on your UNO you are going to use to control the Tx/Rx state of the MKR485. Usually only one pin is needed to drive both the /RE and the DE pins that control the direction of flow of the data. Whichever pin you use, connect it to MKR485 A5 & A6.

I think that’s pretty much it. Just remember to call the serial flush() function before switching back to receive mode.

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