In this article, I’ll upgrade a Philips CDI450 with 32 KB NVRAM. You’ll find all information that is needed to modify the system ROM and the mainboard. If this sounds familiar – yes, it does: In 2019, I explored the possibility to upgrade a CDI470. Even though patching the system ROM failed back then, the experiment was still a success. The final solution to access 32 KB NVRAM was to use the ROM of a 490. As it turned out later, this was also Philips’ solution for the 470/85 model, but that is a topic for another article.
With the 450 (and all other top-loading players with Roboco mainboard) it is a bit different: It’s a low-cost model with 8 KB NVRAM only. The mainboard was neither prepared for a bigger NVRAM solution nor is there a similar advanced model that I could borrow the system ROM from. This time, a ROM patch must succeed.
This guide shows the replacement of the laser sledge in Philips CDM 12.1T CD mechanisms. It assumes that you have already cleaned the lens and done the necessary troubleshooting to rule out other errors (see this article for diagnosis with the Service Shell). If you only get dirty disc messages or experience stuttering audio/video from time to time, you can still follow the guide to clean and grease the mechanism.
For documentation, I replaced the laser sledges of two CDI450 players with unreliable or no disc recognition at all. I took different approaches to find the easiest replacement procedure, so don’t be surprised if you suddenly see pictures where things are in different places.
This is an overview of the lists of capacitors and other components that I had to create in order to repair or modify my devices. Currently, all of them are already featured in my repair articles, but I will add further lists that are not featured yet or are a work in progress.
When I made my MV2FS ready for home-use, I also added a ball top to my Neo Geo CD Controller Pro. This was supposed to be handled in an article in 2018, but it somehow got lost. Anyways, here it is:
The SNK Neo Geo CD Controller Pro (aka kidney bean stick) doesn’t have a regular ball top like the arcade stick. Instead, it has an indented head, probably to rest your thumb on.
Recently, I acquired yet another CD-i player for repair and it came with a Philips 22ER9021 CD-i Gamepad. The gamepad showed two common signs of usage: Broken cable insulation and an unresponsive D-Pad.
The coating is broken right behind the cable strain relief. I’ve seen much worse cases of broken insulation and even ripped out conductors, but this still needs to be fixed before it becomes worse.
Philips 22ER9021 PCB – front – with broken cable insulation
For quite some time, I was puzzled why my CDI660 was stuck in a reset loop after I inserted the test/dummy plug into Input 1. I expected it to boot into the Service Shell, like most other CD-i players. My solution so far was to use a 490 system ROM in the 660 whenever I needed the Service Shell (the compatibility and also the error were discovered during this experiment). However, this wasn’t a very practical approach because I had to open up the player and dig out the system ROM from underneath the DVC every time.
When CD-i Emulator with -testplug option showed the same behaviour, CD-i Fan figured out what is causing this error: The Service Shell module sv is missing from the 660/670 system ROM. In this article, I will show you a simple ROM patch to enable the Service Shell for the CDI660.
In the early to mid-90s, the Texas Instruments Ti-82 Graphics Calculator (or Graphing Calculator) was introduced and became a requirement in some high schools. I never had the official serial link cable to connect mine to a PC, but it came with a calculator-to-calculator link cable. That cable was very popular during math lessons for trading pictures, programs and games. We had several games back then, but I only remember one game, a Breakout clone programmed in TI-BASIC that was painfully slow.
I still have this calculator, but it was sitting in a drawer for more than 20 years. In this article, I will bring it back to life and connect it to a modern Windows 10 PC to install a Breakout clone or something better on it.
The second generation professional and authoring CD-i players of the Philips CDI60x series feature a DE-9 RGB port. To improve the video quality of my CDI605T/20 and also to prepare for future experiments, I built a prototype RGB SCART adapter. The needed pinout is documented in the 605 and 605Tuser manuals on ICDIA.
Philips CDI605 RGB SCART adapter – prototype
After the first tests were successful, I made this schematic for an adapter with a SCART socket (output) for both RGB video and audio:
I recently acquired a cheap Top Hunter MVS cartridge with graphic glitches for repair. When I plugged it into my Neo Geo MV2FS, it had the mentioned graphic glitches and a mostly green-tinted image.
This Hori Joystick-7 (HJ-7) for the Nintendo Famicom has been sitting on my shelf for many years. When I finally took it out to use it for the first time, I noticed that the stick got stuck when moving it all the way to the left or right. In this article, I will open it up and fix that issue.
