Hello!
I found a schematic diagram of the Model 3 Step 2 video board at
https://github.com/MisterTea/MAMEHub/bl ... s/model3.c:
which I will include at the bottom.
If I compare it to actual photos of a Model 3 Step 2 Video board, the schematic seems way larger and extended at the bottom.
For example, there's the usual half-circle of 4x Sega 315-6060 "Mars"-chips present, which you can see on the actual board.
But at the bottom of the schematic image, two more 315-6060s are listed.
Can anyone tell me what's going on there?
See the following screenshot:
Edit: I made it clearer in the picture what I mean.
I ask this because on the page segaretro.com , it lists the Model 3 board having 6 of those 315-6060 "Mars"-Rasterizer-processors without giving any source or merely, the sources they give do not confirm this.
Wanted to check if it is true or not, but all I could find was this schematical image of the board, which does not seem right.
Model 3 Step 2 board schematics
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Re: Model 3 Step 2 board schematics
For comparison, this is the annotated video board that model3man posted in the old forums.
Dark blue is Mars (315-6060 + assigned RAM):
Dark blue is Mars (315-6060 + assigned RAM):
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Re: Model 3 Step 2 board schematics
Whoever came up with that schematic accidentally duplicated many of the lines. Here's what it is supposed to look like:
Code: Select all
|---------------------------------------------------------------------------------------------------|
| |
| D4811650GF D4811650GF 33MHz M5M4V4169 M5M4V4169 M5M4V4169 M5M4V4169 |
| D4811650GF M5M4V4169 M5M4V4169 M5M4V4169 M5M4V4169 |
| M5M410092FP |
| (TQFP128) M5M4V4169 |
| SEGA SEGA M5M4V4169 |
| SEGA 315-6058 315-6060 |
| 315-6057 (BGA) (BGA) M5M4V4169 |
| SEGA (BGA) M5M4V4169 |
| 315-6022 |
| (QFP208) KM4132G271AQ-10 SEGA SEGA |
| (QFP100) 315-6059 315-6060 M5M4V4169 |
| (BGA) (BGA) M5M4V4169 |
| |
| |
| M5M410092FP M5M410092FP M5M4V4169 |
| SEGA (TQFP128) (TQFP128) M5M4V4169 |
| 315-6061 M5M410092FP |
| (BGA) (TQFP128) M5M4V4169 |
| M5M410092FP M5M4V4169 |
| (TQFP128) M5M410092FP |
| (TQFP128) SEGA SEGA M5M4V4169 |
| SEGA M5M410092FP 315-6059 315-6060 M5M4V4169 |
| 315-5648 (TQFP128) M5M410092FP (BGA) (BGA) |
| (QFP64) (TQFP128) SEGA |
| 315-6060 M5M4V4169 |
| (BGA) M5M4V4169 |
| |
| M5M4V4169 |
| M5M4V4169 |
| ADV7120KP30 |
| (PLCC44) |
| M5M4V4169 M5M4V4169 M5M4V4169 M5M4V4169 |
| M5M4V4169 M5M4V4169 M5M4V4169 M5M4V4169 |
| |
|---------------------------------------------------------------------------------------------------|
Re: Model 3 Step 2 board schematics
Yes... I had that impression as well, maybe an error when pasting. Thank you for clearing this up.