K8055N Digital Outputs

Hello community,

I bought the K8055 yesterday…

I finish the building and want to test all in/outputs…

All inputs work fine, analog outputs work fine but the digital outputs dont work(the system LED work fine).

All digitaloutputs are at no cross = 0.
If i conect a extern LED to output 1 (-) and the (+) to DAC2 output the LED switch on and i could not switch off the LED.
If i switch output 1 to on the system LED switch on so i think the IC work fine.

How can i fix it?

sry 4 my english…

The digital outputs of the K8055 are open collector. Do you know what that means?

Regards,
Jan