Carnivore2 announcements | MSX Resource Center (Pagina 6/15)

Guardian (3571)

12-08-2020, 17:16

Your monitor is aligned for width 37, which is the default resolution for your text screen. With width 40 and with Carnivore2 inserted, you will always go off the left boundary.

Van Grauw

Ascended (10716)

12-08-2020, 17:30

Nprod wrote:

WIDTH 40 doesn't change anything, but WIDTH 37 does shrink it to a more reasonable level. I don't see how it could be a monitor/TV issue since the built-in BASIC ROM has always shown up normal. In fact, if i boot into the built-in BASIC and type WIDTH 40, it gets stretched off screen just like on the Carnivore2.

If you play any kind of game, you will also note that pixels are being clipped off the left border.

Text mode width 37: 222 pixels wide (left edge offset by 20 pixels)
Text mode width 40: 240 pixels wide (left edge offset by 8 pixels)
Graphic modes: 256 pixels wide (max)

If you type SCREEN 1:COLOR 15,4,7 you will be able to clearly see where the borders of the active display area are. Blue is the active display area that should be fully visible. Cyan is the overscan border that can disappear into the monitor’s edge.

What’s the brand / model of your monitor? Does it have adjustment pots on the back?

Van sdsnatcher73

Prophet (3851)

12-08-2020, 17:32

Nprod wrote:

I don't get it, if the monitor is misaligned why would i get two different results depending on whether the cart is inserted or removed?

I agree, it seems the cartridge has some effect on your machine’s video output. Two things that come to mind:
1. Power supply that may be insufficient to supply all components (including the extra components in C2)
2. Clock drift may occur (although I can’t really say how that affects the timing of the sync pulse

Van Nprod

Expert (100)

12-08-2020, 17:38

So the carnivore and its Nextor BASIC use width 40 by default, while everything in the factory roms uses width 37? Strange... I also use this TV set with a Commodore 64 and its frame aligns perfectly in the center. If i fiddle with the pots on the TV, anything i hook up that is not the HB75+Carnivore will get shifted to the right...

sdsnatcher73 wrote:

I agree, it seems the cartridge has some effect on your machine’s video output. Two things that come to mind:
1. Power supply that may be insufficient to supply all components (including the extra components in C2)
2. Clock drift may occur (although I can’t really say how that affects the timing of the sync pulse

That sounds a lot more plausible.

Van sdsnatcher73

Prophet (3851)

12-08-2020, 17:45

Nprod wrote:

So the carnivore and its Nextor BASIC use width 40 by default, while everything in the factory roms uses width 37? Strange... I also use this TV set with a Commodore 64 and its frame aligns perfectly in the center. If i fiddle with the pots on the TV, anything else i hook up to it will get shifted to the right...

Okay it may be that indeed the C2 sets the width to 40 by default to display the boot menu and messages. If the machine boots without C2 and you perform a width 40 the O from the Ok prompt also disappears?

The alignment of your MSX may be different than other computers but that is not affected by the C2 then. You may be able to adjust the alignment with some of the pots in the computer but I am not sure.

I have tried many MSX machines and they all have slightly different alignment.

Van Wierzbowsky

Guardian (3571)

12-08-2020, 18:02

Are there any other controls on your monitor's back? I remember that some monitors had additional buttons to switch modes, maybe the monitor needs a different mode?

Carnivore2 indeed sets screen 0 and width 40. I will create a ticket for setting the default screen resolution from BIOS upon exit from C2's Boot Menu.

Van Grauw

Ascended (10716)

12-08-2020, 18:09

Alexey: also restore screen mode then, Japanese MSX computers boot to screen 1 by default.

However this won't fix your underlying issue Nprod. I find the power supply / clock drift explanation implausible, especially if you get the same at width 40 without Carnivore2 inserted.

Van Nprod

Expert (100)

12-08-2020, 18:08

Alexey wrote:

Are there any other controls on your monitor's back? I remember that some monitors had additional buttons to switch modes, maybe the monitor needs a different mode?

I will create a ticket for setting the default screen resolution from BIOS upon exit from C2's Boot Menu.

It's just a regular home TV set, it has no geometry adjustment controls unless you take the back cover off (which i'd rather not do). And as i said, every other computer i've used with it like the C64 works fine, so this is something specific to the HB75.

Thanks for creating the ticket - it's not the end of the world, but it's still an issue that's worth looking into. Are there any other HB75 owners on here with a Carnivore2 that can confirm this behavior?

Van Grauw

Ascended (10716)

12-08-2020, 18:37

Grauw wrote:

If you type SCREEN 1:COLOR 15,4,7 you will be able to clearly see where the borders of the active display area are. Blue is the active display area that should be fully visible. Cyan is the overscan border that can disappear into the monitor’s edge.

Have you tried this? SCREEN 1:COLOR 15,4,7

Please try without Carnivore2. Also while in screen 1 you can type WIDTH 32 (maximum width of screen 1) to make the text go entirely to the borders. Make a photo of this with and without Carnivore2 for comparison.

Note we’re talking about old analog equipment here and the calibration can be off after so many years. So taking the panel off for a tuning doesn’t sound unreasonable to me. I don’t know about the C64. I just know that inserting a cartridge is very unlikely to change the video output in a way that the entire active display area is shifted.

I have a HB-75P with RGB SCART, but I'll have to dig it up from my storage room.

Van Nprod

Expert (100)

12-08-2020, 18:41

I just tested it, "SCREEN 1:COLOR 15,4,7" gives the same result whether the carnivore is inserted or not. Setting width to 32 causes the text to go off to the left both with and without the cartridge in.

So the behavior is different only for Screen 0, where width should be 37, but the C2 sets it to 40.