[Coco] Modern monitors that work on CoCo 3 and MM/1

L. Curtis Boyle curtisboyle at sasktel.net
Wed Mar 12 23:06:06 EDT 2025


We do actually have a flag in the source that can be set to change it when assembling. But it might be easier/faster to just DED or KWIKZAP /dd/cmds/grfdrv. Are you running the 6809 or the 6309 version of EOU? The offsets to change will be different between the CPU versions.

L. Curtis Boyle
curtisboyle at sasktel.net

TRS-80 Color Computer Games website
http://www.lcurtisboyle.com/nitros9/coco_game_list.html

NitrOS-9 Ease of Use (EOU) Project
http://www.lcurtisboyle.com/nitros9/nitros9.html




> On Mar 12, 2025, at 8:23 PM, Christopher R. Hawks <chawks at dls.net> wrote:
> 
> On Wed, 12 Mar 2025 18:22:51 -0600
> "L. Curtis Boyle" <curtisboyle at sasktel.net> wrote:
> 
>> We do set the GIME to add an extra line between text rows (all 25 of
>> them, not 24) to make them more readable (descenders won’t touch the
>> tops of characters on the line below). So we are essentially running
>> 320x224 / 640x224 pixels in the hardware text modes.
>> 
>> Graphics modes are 320x199  640x199, so they don’t have the extra
>> space.
>> 
>> L. Curtis Boyle
>> curtisboyle at sasktel.net
>> 
>> 
>> 
>>> On Mar 12, 2025, at 5:36 PM, Christopher R. Hawks via Coco
>>> <coco at maltedmedia.com> wrote:
>>> 
>>> On Thu, 6 Mar 2025 20:57:31 -0600
>>> Allen Huffman via Coco <coco at maltedmedia.com> wrote:
>>> 
>>>>> On Mar 6, 2025, at 8:48 PM, Christopher R. Hawks via Coco
>>>>> <coco at maltedmedia.com> wrote:
>>>>> 
>>>>>  AND freesync ONLY works with HDMI and Display Ports! So the
>>>>> 'freesync' part is moot for the CoCo RGB. G-Sync is only on
>>>>> Display Ports (v1.2a).
>>>>> 
>>>>>  What matters is if the VGA port will take a 15KHz signal. I have
>>>>> a couple that do and one on the way that will. None of them are
>>>>> freesync or G-Sync. Most of the previous monitors only sync down
>>>>> to 30 KHz.
>>>>> 
>>>>>  Hopefully, the 'sync's will guarantee that ALL inputs can sync
>>>>> to 15 KHz...
>>>> 
>>>> 
>>>> The plot thickens. Thank you for shedding light on this!
>>>> 
>>>> --
>>>> Allen Huffman - PO Box 7634 - Urbandale IA 50323 - 515-999-0227
>>>> (vmail/TXT
>>>> only) http://www.subethasoftware.com - https://www.facebook.com/subethasoftware
>>>> 
>>>> 
>>>> 
>>> 
>>>   Took delivery of the new monitor yesterday. It does work with the
>>> 15KHz signal, BUT!
>>> 
>>>   The displays from BASIC (24 lines, WIDTH 80) and NitrOS9 (24
>>> lines) are a bit low on the screen. EOU (25 lines) is so low on the
>>> screen that half of the last line is OFF THE SCREEN.
>>> 
>>>   Is EOU mucking with something else?? Vertical for BASIC and
>>> NitrOS9 start and end at the same place on the screen, but, EOU
>>> starts 2 lines higher and the bottom half of line 25 is off screen.
>>> 
>>>   The vertical position setting on the monitor only moves the
>>> display a few pixels.
>>> 
>>> Christopher R. Hawks
>>> HAWKSoft
>> 
>> 
> 
> Curtis:
> 
>    Thanks for the explanation. Since this monitor displays a bit low
> from center, part of the last line is off screen. It 'should' center
> the image horizontally and vertically (or at least allow a range of
> position changes. Horizontal can move the image about 2 inches. Vertical
> can only change the position 1 pixel up or down. It goes 0  50 100,
> only 3 steps.
> 
>    Other than that, it's a great ViewSonic monitor for only $75 with
> free shipping.
> 
>    Too bad I can't compile a version without the extra lines...
> 
> Christopher R. Hawks
> HAWKSoft
> -- 
> "Love is a snowmobile racing across the tundra and then suddenly it
> flips over, pinning you underneath. At night, the ice weasels come."
>              --Matt Groening
> ----------------------------------------
>       \   ^__^                         
>        \  (oo)\_______                 
>           (__)\       )\/\           
>               ||----w |                
>               ||     ||                
> 



More information about the Coco mailing list