As there are a few boards out there now for testing thought I would put up a guide on how these currently work.
Using the board on the H4 it plugs into the Shifter socket but there is also a VSYNC pin that is exactly in line with the VSYNC on the H4 motherboard. That pin should have a single socket to plug into. If you already have a VGA port or ST Monitor port soldered into your H4 then you will have to stack the board with DILs and you can put a wire from the VSYNC point down to the VSYNC on the H4.
The three LEDs marked show the frequency of the display being shown i.e. 50/60Hz for Low / Med and 71.2Hz for Mono.
JP1 - this jumper allows you to alter various setting on the board:
- Yellow - 0 = Borders, 1 = No Borders
- White - 0 = 4:3 ratio, 1 = 16:9 ratio
- Green - 0 = No scan lines, 1 = Adds old CRT looking scan lines
These two together provide the following options. Note that resolution is what the monitor / TV is operating at the ST resolution is using those numbers. The board does not give you anything other than the standard Low, Med and High resolutions within those TV display ratios:
Borders | Ratio | TV Res |
0 | 0 | 800x480 |
0 | 1 | 480p |
1 | 0 | 720x400 |
1 | 1 | 640x400 |

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