SX1509 issues

Development Boards Arduino
1

I’m working on interfacing the SX1509 I2C GPIO board with the Arduion. I’ve wired up SDA, SCL, 3.3V and GND. A pushbutton is wired to pin 1 (and GND), and and LED is wired to pin 14 (and GND). Board address is 0x3F (and set correctly in the sketch).

Using the example provided, I compile, upload, then - nothing. No flash of the LED, no recognition of the pushbutton. I’ve tried this on two separate SX1509 breakouts.

Anyone have any luck with these things?

2

I’ve not used the BoB but I see a couple of potential problems.

  1. The default address (per the schematic) is 0x3E. Did you change a solder jumper to get 0x3F ?

  2. What voltage is your Arduino ? The 3.3V high is awfully closer to the limit for a logic high on a 5V 328P. I wonder if you shouldn’t undo SJ5 and use external pull-ups to 5V instead.

It would be easier to examine your code if you posted it.

3

Fantastic, Mee_n_Mac, thank you so much!

Yes, I changed the solder jumper, but I changed the wrong one - that’ll teach me to start projects at 6pm on a Friday.

I’m using an Arduino UNO R3 - so, 5volts. I disconnected the 3.3V pullups (SJ5) and added the 4.7K pullups to 5v - everything works a treat!

The sketch I am using is the Digital Read/Write Example from Jim Lindblom.

Thanks again!

4

Kewl !

It’s always the simple things that bite you in the butt.

5

"'m working on interfacing the SX1509 I2C GPIO board with the Arduion. I’ve wired up SDA, SCL, 3.3V and GND. A pushbutton is wired to pin 1 (and GND), and and LED is wired to pin 14 (and GND). Board address is 0x3F (and set correctly in the sketch).

Using the example provided, I compile, upload, then - nothing. No flash of the LED, no recognition of the pushbutton. I’ve tried this on two separate SX1509 breakouts."

I am having exactly the same problem as described above. Unfortunately though, being newer to this, I dont really understand the discussion and the solution! Would you mind elaborating a little for me?

The example sketches are easy enough for me to follow, but when it doesnt work, Im stumped. If you could help me out I’d really appreciate it. Thanks.