Atari ST Computer
Monitor Port
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| Pin | Description |
|---|---|
| 1 | Audio Out Comes from the amplifier connected to the output of the sound chip. A high-impedance earphone can be attache here if you do not use the original monitor. |
| 2 | Not used |
| 3 | General Purpose Output Available for your use. The line has TTL levels and comes from I/O port A bit 6 of the sound chip. |
| 4 | Monochrome Detect If this line, which leads to the 17 input of the MFP 68901, is low, the computer enters the high-resolution monochrome mode. If the state of the line changes during operation, a cold start is generated. |
| 5 | Audio In Leads to the input of the amplifier described in 1 and is there mixed with the output of the sound chip. |
| 6 | Green Analog green output of the video shifter. |
| 7 | Red Analog red output of the video shifter. |
| 8 | Ground |
| 9 | Horizontal Sync Responsible for the horizontal beam return of the monitor. |
| 10 | Blue Analog blue output of the video shifter. |
| 11 | Monochrome Provides a monochrome monitor with the intensity signal. |
| 12 | Vertical Sync Takes care of the beam return at the end of the screen. |
| 13 | Ground |