I got a GrovePi+ board and an LCD RGB Backlight. When I hook it up I notice two extra I2C addresses appear in i2cdetect result.
0x03 - unknown
0x62 - rgb
0x3e - characters
0x70 - unknown, and this one disappears sometimes
What are those two extra addresses? I really did quite a research and haven’t found an explicit answer yet.
Can you post here the results of the following procedures:
i2cdetect command with the GrovePi & with the LCD RGB
i2cdetect command with the GrovePi & without the LCD RGB
Also, please make sure you have plugged in the GrovePi on top of Rapberry properly - if you haven’t, then things might happen.
Also, you should make a firmware update to the GrovePi.
If you don’t have the
Raspbian for Robots image, then I highly suggest using it asap.
After you’ve installed the
Raspbian for Robots image, open up a terminal and follow this commands:
sudo bash firmware_update.sh
The last lines you get should look like this:
Here’s one advice I usually give: do everything meticulously and always follow the procedure - even if it sounds redundant at times - it will save you.
I have updated quite recently with the dexterindustries script, also the firmware is up-to-date.
I’m not complaining that it’s not working. it’s perfectly working does what I want. But I would like to get some information about those extra I2C addresses.
Just point me to the right direction / datasheet! Thanks!
Thank you for your answer.
The RGB LCD has 2 chips with 2 different functionalities. One of it drives the LEDs and the other one drives the text that’s printed.
The text driver is one and only and has an address of
The LED driver has multiple addresses, of which we only need one. As it’s specified on page 8 (annex 7.1.1) in this datasheet (aka PCA9633), there are 3 fixed addresses for our 8-pin chip package (the PCA9633):
LED all call address - it’s on at startup and cannot be addressed individually
Software reset address - it’s on at startup and cannot be addressed individually
Slave address - it’s the one you are communicating with and is addressable
Hope everything is crystal clear now.
Exactly what i needed.