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TassyJim

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Posted: 08:45pm 13 Apr 2023

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TV monitors were designed to deliberately hide the edges of the display area so the viewer wouldn't see the usually flickering edges. Loosing a bit of the scene was not important.

When monitors started to get used for computers, they were equipped with an overscan/underscan setting. This was sometimes called PC mode etc and allowed the full display to be visible.

It looks like the new fangdangled monitors have forgotten about PC requirements again.

As far as VGA to HDMI adapters. There are many HDMI standards to choose from. The adapters readily available all look the same but can claim to be for a different revision of HDMI. That might make a difference.

Jim

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hitsware2

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Posted: 09:44pm 13 Apr 2023

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mclout999 said
There is some form of protocol in monitors
that provides information like native RES
and available refresh rates.

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circuit
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Posted: 09:31am 14 Apr 2023

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TassyJim said TV monitors were designed to deliberately hide the edges of the display area so the viewer wouldn't see the usually flickering edges. Loosing a bit of the scene was not important.

When monitors started to get used for computers, they were equipped with an overscan/underscan setting. This was sometimes called PC mode etc and allowed the full display to be visible.

It looks like the new fangdangled monitors have forgotten about PC requirements again.

As far as VGA to HDMI adapters. There are many HDMI standards to choose from. The adapters readily available all look the same but can claim to be for a different revision of HDMI. That might make a difference.

Jim

This was my thought exactly - the issue of overscan/underscan which gives clean edges on the monitor when viewing films etc. by cropping the edges sharply. I was about to suggest this when I saw Jim's posting. The first few lines and last few lines on broadcast transmissions have been used in the past for data and if viewed through a full screen computer monitor they could be seen flickering away at the top and/or bottom of the screen like some form of extreme morse code. The overscan/underscan dated from the days of cathode-ray tube screens when televisions and some monitors had all the old analogue controls (vertical hold and so forth) and the old Teletext data could be seen or cropped out with vertical adjustment. And yes, one of my older monitors has overscan/underscan options which I used to deal with one column clipping on a VGA signal from a computer board in the past.

mclout999
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Posted: 07:46pm 14 Apr 2023

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Mixtel90 said You aren't going to get the CMM2 to read the monitor data or to send config data to it. That's done over a digital interface that isn't there. The CMM2 is generating VGA to spec, as far as I know, or at least within normally acceptable tolerances and HDMI isn't an option (IIRC it uses LCD display hardware on the chip to generate VGA instead).

I have a horrible feeling that the CMM2 simply isn't compatible with that fancy monitor.

It's not just that monitor I have tried it on 2 TVs and 3 monitors with HDMI inputs. and have tried 3 of those VGA to HDMI adapters. I even got a ODV GBS-C form Amazon this morning and it dose not work either and it has screen postion adjustments that just don't work.(it is a video upscaler for reto consoles that has a myriad of adjustments) I think that puts an end to it for me. I spent a lot of time on this and need to MOVE on. It will have to become tolerable or I will slowly stop using my CMM2s.
Edited 2023-04-15 05:49 by mclout999

mclout999
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Posted: 07:55pm 14 Apr 2023

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thwill said I don't pretend to know anything (this sounds suspiciously like hardware), but can you control the aspect ratio on the monitor ? Whilst the CMM2 spits out 4:3 (?) most modern monitors default to some sort of wide-screen.

Best wishes,

Tom

Tried all that and no go. Spent time with manufacture NO GO either. If I turn off all the advanced features(a very tedious procedure to do and undo) I can get it into 4:3 but it is not so great that way either. it is MUCH thinker and cut off on the top and bottom.
Edited 2023-04-15 05:57 by mclout999

matherp
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Posted: 09:38pm 14 Apr 2023

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Buy a cheap VGA monitor - lots available on ebay

mclout999
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Posted: 05:00pm 15 Apr 2023

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matherp said Buy a cheap VGA monitor - lots available on ebay

A little flippant there son!

I have about 10 VGA monitors laying about but only one suitable work space in my tiny condo. If I can't have it at my desk I am not going to find it easy to use it at all. Not everyone has optimal space in their situations. I asked the community and they help or chimed in and that is after all what this forum is for I believe. I love my CMM2s and thank you for all your work on them. I remember but can not seem to find the thread on this issue from the past and that you said that he implementation of VGA was a very elegant, simple, and affordable method and that it would be difficult or imposable to address this issue. That is why I was asking others if they had an VGA to HDMI adapter the did not have the right shift issue. I mean I just dropped a $100 on a video converter/upscaler to see if it would help and spent a week trying to find a solution for this and my particular situation. I thought that maybe other might have the same issues and could benefit from finding a solution to this as newer monitors are going stop having VGA as a option.

Thanks.

thwill

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Posted: 05:23pm 15 Apr 2023

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Have you considered a cheap HDMI capture device and viewing the CMM2 via OBS on your workhorse PC ? This is what I do when using CMM2 or PicoMiteVGA at my "day job" desk.

EDIT: That said I suspect there is some underlying issue, perhaps with your specific CMM2, that is beyond my pay grade

Best wishes,

Tom
Edited 2023-04-16 03:30 by thwill

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Mixtel90

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Posted: 05:51pm 15 Apr 2023

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I suspected that a dedicated monitor wasn't what was required so I didn't suggest it. :)

I'm not certain that, even with a correctly working converter, the end result would be all that good. They are really intended to give a passable picture from something like a DVD player or an almost acceptable one on a projector from a laptop. Whether you can get one that would give text comfortable to work with for any length of time I'm not sure. I've converted the other way, from a Raspberry Pi to a VGA monitor and that wasn't too bad (not as good as a HDMI monitor though).

I know there are several different HDMI versions. I suppose you need to find a converter that suits your particular TV.
https://www.pcmag.com/encyclopedia/term/hdmi-versions

There is another point - whether any given converter will be able to scale the various VGA resolutions correctly.

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matherp
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Posted: 06:39pm 15 Apr 2023

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mclout999

Try this

CMM2V1.5.zip

Load the new firmware, you may get a garbled screen so before anything else note your current options (OPTION LIST) and then type

OPTION RESET

Then you can use a new command

OPTION HORIZONTAL OFFSET mode, offset

mode is the screen mode you want to tune (1 to 18)
offset is the offset in pixels to move the display horizontally (-128 to 127)

Appendix G of the manual if you have forgotten how to update the firmware
Edited 2023-04-16 07:29 by matherp

mclout999
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Posted: 09:49pm 15 Apr 2023

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thwill said Have you considered a cheap HDMI capture device and viewing the CMM2 via OBS on your workhorse PC ? This is what I do when using CMM2 or PicoMiteVGA at my "day job" desk.

EDIT: That said I suspect there is some underlying issue, perhaps with your specific CMM2, that is beyond my pay grade

Best wishes,

Tom

Thanks for the suggestions and I may try that if the update That matherp just dropped with a setting to help. I am off to try that now. He is freaking amazing.

mclout999
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Posted: 09:57pm 15 Apr 2023

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matherp said mclout999

Try this

Well I did not expect this and I am thankful for it and will get right to it and will give a follow-up with the outcome. This could be a very good thing for some CMM2 users. You are awesome whatever the outcome. I will try it on all my adapters and 5 different monitors/TVs. I really do appreciate all that you do. Thanks.

toml_12953
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Posted: 10:26pm 15 Apr 2023

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matherp said mclout999

Try this

CMM2V1.5.zip

Load the new firmware, you may get a garbled screen so before anything else note your current options (OPTION LIST) and then type

Does this replace CMM2V5.07.02b9?

mclout999
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Posted: 12:15am 16 Apr 2023

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OK, the new option works for most modes and I love it. I had to go through all the mode for the first time and find the best offset and did not know that a few mode don't work on the old or new firmware to begin with. I tried it on all 5 displays and it is all very consistent. I left one of my Gen 1 on the old firmware for testing. Mode 7 is way over to the right and offsets just make it display nothing. Mode 10 was slightly high cutting about half the top line but H-offsets work fine. mode 14 and 18 have the same issue as 7. This is fine for most mode every other mode can display perfectly now with offsets and they are persistent on power cycles. I will experiment later with some of those modes that are an issue with the old Firmware and new. This was a great outcome. I wonder if any of those modes that have an issue are even used much. Anyone have input on that? Thanks all and thanks Matherp a lot.
Edited 2023-04-16 14:22 by mclout999

matherp
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Posted: 06:58am 16 Apr 2023

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Typo in mode 7 fixed below. Mode 18 won't work on most monitors. Mode 14 should - works perfectly for me on a real VGA monitor.

CMM2V1.5.zip
Edited 2023-04-16 18:05 by matherp

mclout999
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Posted: 04:21pm 16 Apr 2023

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matherp said Typo in mode 7 fixed below. Mode 18 won't work on most monitors. Mode 14 should - works perfectly for me on a real VGA monitor.

CMM2V1.5.zip

Thanks. I will test today. Mode 14 was good on all the VGA monitors of or TV I had before. I will thinker with that mode as well.

EDIT:

Mode 7 is great. There is one thing but not worrying about it but I wanted you to know. Mode 10 can be shifted ok but the fonts are a little gabled. Thanks again.
Edited 2023-04-17 04:36 by mclout999

mclout999
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Posted: 06:48pm 16 Apr 2023

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Next issue. I think this has been covered somewhere else but I flashed to new firmware to my Gen 2 and all is well. I then flashed it to one of my Gen 1s and it was good too. The second Gen 1 flashed and the STM32CubeProgramer said it was successfully done but it will not boot. I reflashed it with the beta 9 firmware and same issue. I is outputting a 600*800 signal for my monitor to latch on to but it is just a blank screen and my keyboard dose not power up. WHAT HAVE I DONE!!!! Did I brick it or are there some things I can try. HELP!!!!!

I also removed the RTC to make sure it forgot it's setting but the KB not powering up is suspect. Thanks

JohnS
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Posted: 07:10pm 16 Apr 2023

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I think it can't be bricked (at least not that way). Worst case there are other tools (texane stlink etc) which can re-flash it.

John

mclout999
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Posted: 11:04pm 16 Apr 2023

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JohnS said I think it can't be bricked (at least not that way). Worst case there are other tools (texane stlink etc) which can re-flash it.

John

Ok, what do you mean? I guess it is not technically bricked as the flashing prosses is still accusable The programing software connects to the CMM2 I select ether the new or old firmware and I watch it as it programs the system and verifies it just like it did on the Gen 2 and the other Gen 1. It says it was successful and I shut it off and set the jumper back to boot and all I get is a blank screen. What am I missing and I do not know about those tools you mentioned. Thanks for any help you can give.

TassyJim

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Posted: 11:12pm 16 Apr 2023

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Have you selected "Full chip erase"?

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MMedit MMBasic Help

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