Last year, I asked myself whether or not all Philips 22ER9021 CD-i Gamepads are the same and answered with probably. Since then, I have had a look at some more gamepads of different production dates, including an unbranded 22ER9021 and a TecnoPlus TP520 CD-i Control Pad. Let’s revisit and elaborate on what has been discovered last year:

• The production number on the label contains the year and calendar week (example: 1A 00 9447). This applies to almost all Philips CD-i players and accessories. So far, only the white mice for the professional players didn’t follow the year code.
  A full production number has 8 or 9 digits and an additional 5-6-digit serial number at the end. But most accessories are only labelled with simple 8-digit production numbers and that’s why you find so many accessories with the very same data on the labels.
• Inside, all 22ER9021 gamepads have the same PCB with these markings:
  CDI JOYPAD REV 1.2
  P/N:12290210001-03
  This is still the case after checking some more, even uncommon variants. Also, they all have the same Philips PCA84C122AT/071 8-bit microcontroller for remote control transmitters.