In SX Microcontrollers, SX/B Compiler and SX-Key Tool, lboucher wrote:

Hi All
 

I was hoping someone could help me out with trying to control the PCA9622 with the SX28.

The PCA9622 is a 16 channel LED controller and you communicate with it via I2C. I attached the datasheet.

 

I have never used I2C or this LED controller before.

 

I got everything wired up and spent a few hours trying to get my LED's lite up last night and it just doesn't seem to work.

 

Hardware Setup:

I am using the tssop version.

I have SDA and SCL pulled high via 10k resistors like in Figure 17, and also connected to RC.0 and RC.1.

I have OE pulled low via a 10K resistor.

The A0-A6 pins are set exactly like Fig 17. which should result in an I2C address of 0010101x.

I have LED8-15 hooked up, 1 led and 1 resistor Vdd=5

Due to limited space on breadboard i left LED0-7 disconnected.

 

Firmware Side:

I am following figure 14,

Do

I send a I2Cstart

Then I2Csend 42  which should be correct to write to 0010101x

Then I2Csend 162 which should be the correct control register setting for the sequence in Fig 14.

Then i write out 16 bytes.

Then send I2Cstop

loop

 

I am at work right now, will attach code when i get home.

Do i have to write to MODE1 and MODE2 registers?

I don't see any requirement to, if all i want to do is PWM controll of all 16 leds.

I completely don't care about grouping or all call or anything like that.

 

 

(Note: the one thing that is an unknown. I hand soldered the tssop package to a breakout board. So it is possible I overheated it, but i have 2 units and both won't work. I consider it slightly less likely that i damaged both units.)

 

Also note i have quadruple checked all connections.

I do see the I2Cstart/end events with a multimeter, i have no scope.

 

Any help will be greatly appreciated.

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