Our final product did not work up to our proposed specifications. It did record pulses from OEM remotes, and it did play them back. The VCR that we are testing our device with receives the IR pulses and behaves appropriately. Unfortunately, our inexact replication sometimes makes the button appear to be pressed multiple times (it will turn on then off immediately). Perhaps, it did not recreate them precisely enough to be interpreted by OEM receivers correctly. Looking at an oscilloscope, our recreated waveforms are nearly identical to the OEM generated ones.
One of our problems was too weak an infrared transmitter. The project must be close to the VCR and aimed directly at it to work.
Also, our IR messages were played back with more noise than appeared in the original signals.
We discovered that the 8535 did not have enough memory to record complex signals for 30 seperate buttons as we had originally planned. All IR signals turned out to be far more complex than we had guessed. Realistically, it had enough memory for about 5 different buttons.