How to upgrade an Amiga 600...
|Does the Amiga like TFT screens?
The Amiga 600's ECS chipset is capable of displaying fairly high resolutions of up to 1280 x 512 pixels. However this is only possible in so called interlaced modes that produce a quite annoying "flicker" and require 15 kHz capable or multisync monitors. Most current TFT screens cannot display those modes.
ECS however also provides some real VGA modes that can be displayed on VGA/TFT screens. However those modes restrict the color depth to 16 colors in lowres and 4 colors in highres mode. Also, they quite considerably slow down the machine. Therefore, those modes were never popular with ECS Amiga users.
Due to these issues, "Flicker fixer cards" were soon developed for the larger Amigas and plugged into their video slots. The Amiga 3000 even had a flicker fixer chip called "Amber" on board. Those cards stored two of the interlaced images in a memory space and displayed them as one image with twice the frequency thus eliminating the flickering. This led to speedy high resolution graphics displays without color restrictions.
The large Amiga models 2000, 3000(T) and 4000(T) also could be equipped with "real" graphics cards that have own fast graphics processors and can display high resolutions at 16 million colors. Therefore Flicker fixers soon became second choice for those models. The smaller Amigas like the A500, A1200 and the A600 this website is about, could not be equipped with such graphics cards. Flicker fixers are here still the best choice for a nice and flicker free image.
Until recently, the only available flicker fixer for the Amiga 600 was the "Indivision", an external card developed by Individual computers that was plugged into the external video port of the Amiga 600. The Indivision however didn't produce a very clear image and couldn't deflicker the higher Amiga resolutions like SuperHires Lace (1280 x 512).
Only a few weeks ago (October 2009), Individual Computers released the brand new Indivision ECS card. The Indivision ECS is directly plugged into the "Denise" graphics chip's socket and produces a very clear image. Also, the Indivision ECS can deflicker high resolutions like SuperHires Lace (1280 x 512). Since Indivision ECS is basically a programmable FPGA replica of ECS Denise, it can be freely programmed and its features extended. Indivision ECS is for example capable of emulating the "Graffiti" graphics card and is planned to support the "A2024" display modes (1008 x 1024) soon.
Unfortunately the Amiga 600 is the only ECS Amiga that has a SMD Denise soldered onto its mainboard. In order to be able to use the Indivision ECS, Individual Computer have developed a new memory expansion called "A603" which also provides a clock port (see "USB" section) and a Denise socket. With this expansion, the Indivision ECS can be used in an Amiga 600 computer.
The following steps show how we have upgraded the Amiga 600 with an Indivision ECS card. As often, pictures say much more than words.
If you plan to follow these steps to upgrade your Amiga 600, please be aware that the combination of Apollo 630 processor card and the Indivision ECS is EXPLICITLY NOT supported by Individual Computers! Also, the following steps require a decent degree of soldering capabilities. So please don't underestimate what needs to be done. Chances are VERY likely that one of the cards or even the whole computer get severely damaged!
The first step is to provide proper tools for the task and disassemble your Amiga 600:
1. One of the pins of the A603's socket that is supposed to hold the Indivision ECS is covered by the Apollo 630.
2. The jumpers of the Apollo 630 are too high and prevent the Indivision ECS from being plugged in.
3. The crystal oscillator on the Apollo 630 also is too high.
We tried to solve these problems by heavily modifying the A603, slightly modifying the Apollo 630 and leaving the Indivision ECS unmodified.
First we removed the jumpers on the Apollo 630: