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Re: RGB-connection question??



In article <10DC16A9@rook.wa.com>,
eugene welcome <EUGENE.WELCOME@rook.wa.com> wrote:
> >Hello, I have a friend with an Apple 2c+. I asked me what the pin
> >configuration is,but I honestly have no idea.
> 
> Hi Joe: Here is what I have on the IIc and Laser128 as they were the
> same.  [snip]

The information in your post about the IIc video port is WRONG!

It may be correct for the Laser 128.  The IIc's video port has a set
of internal signals.  The pins listed here might be correct for an RGB
adaptor attached to the IIc video port, but the video port itself does
NOT have any of the signals expected by an RGB monitor (they have to be
generated by an adaptor).

The following table (from your post) is correct for the IIgs, but most
of the listed signals for the IIc are wrong.

>  Apple IIgs RGB                Apple IIc and Laser-128 RGB
>  Pin     Signal                    Pin      Signal
>  ===     ======                    ===      ======
>   1   Ground                        1   Intensity signal
>   2   Red analog video              2   F14M - 14 MHz
>   3   Composite sync                3   Red - signal
>   4   Not connected                 4   Blue - signal
>   5   Green analog video            5   Spkr sound output
>   6   Ground                        6   Load Pulse for LCD
>   7   -5 volts                      7   Dispen for LCD
>   8   +12 volts                     8   +12 volts DC
>   9   Blue analog video             9   Horizontal Sync Signal
>  10   Not connected                10   Composite Video Sync Signal
>  11   Sound                        11   Serial out - Data for LCD
>  12   Composite video (NTSC, PAL,  12   Composite Video Output
>         or SECAM )                 13   Ground
>  13   Ground                       14   Vertical Sync Signal
>  14   Not connected                15   Green - Signal
>  15   Not connected            Note  LCD = Liquid Crystal Display


The actual functions of the IIc video port are as follows:

1   TEXT     Indicates text mode is active (special function in DHR mode)
2   14M      14 MHz clock sigal
3   SYNC     Horizontal and vertical sync
4   SEGB     Vertical counter signal from IOU, or lo-res indication
5   1VSOUND  Sound output (one volt peak-to-peak)
6   LDPS     Video shift load enable
7   WNDW     Active area display blanking
8   +12V     +12 volts DC
9   PRAS     RAM row address strobe
10  GR       Graphics mode enable
11  SEROUT   Serialized character generator output
12  NTSC     Composite NTSC video output
13  GND      Ground reference
14  VIDD7    Bit 7 of video shift latch (for hires mode colour shifting)
15  CREF     Colour reference timing signal

These come from the IIc Technical Reference, both first and second
editions.

It is odd that your listing for the IIc is correct for some of the
signals, but has RGB outputs in place of the IIc's timing signals.


You cannot connect a monitor directly to the IIc video port (with the
possible exception of the the LCD display, or an NTSC monitor).  An
adaptor is required to generate the appropriate video signals for an
RGB monitor.
-- 
David Empson
dempson@actrix.gen.nz
Snail mail: P.O. Box 27-103, Wellington, New Zealand