Introduction

I bought a refurbished 20 inches monitor. It is a RasterOps, but I don’t know the model. Inside, it uses a Hitachi CM2085.

The problem is the connectors are BNC types. The solution is to make a new cable, with sense connected in the right way. I find that the Hitachi CM2085 can do up to 1024×768 at 75 Hz, and it is multiscan. In the Apple video mode, it’s a 16 inches multiscan.

Description

Connection

The sense on the Mac video plug should be connected like this:Sense 0 (pin 10) connected to ground.Sense 1 (pin 7) connected to sense 2 (pin 4) with the diode (the mark next to sense 2).Look at Apple for technote HW30 for more info on sense modes. You’ll need 5 BNC, and a DB-15 male connector (not a high density one), an a diode for example an 1N4148. Here is the connections:

 

DB-15 Mac	Name		Output
1	Red Gnd	——	BNC Red Gnd
2	Red	——	BNC Red
3	/CSYNC
4	sense 2	——	sense 1 (DB-15)
5	Green	——	BNC Green
6	Green Gnd	——	BNC Green Gnd
7	sense 1	——	sense 2 (DB-15)
8
9	Blue	——	BNC Blue
10	sense 0
11	C&VSYNC Gnd	——	BNC VSYNC Gnd
12	/VSYNC	——	BNC VSYNC
13	Blue Gnd	——	BNC Blue Gnd
14	HSYNC Gnd	——	BNC HSYNC Gnd
15	/HSYNC	——	BNC HSYNC

 

Use under differents OS

The Hitachi CM2085 works perfectly with many OS because it is multiscan. It can support resolution from 640×480 to 1024×768.