DOS tool to switch from 50 to 60Hz?

Champion (293)

03-04-2016, 05:58

Does anyone have a DOS tool that changes the VDP to 60Hz? I did some searching and found a tool by Nyrikki that changes the frequency back and forth, but not one I can use to simply force 60hz in an autoexec.bat

Thanks.

By Victor

Champion (509)

03-04-2016, 06:38

Here you have one made by Trunks:

DISPLAY.COM

Usage:

DISPLAY -> This will show you the current VDP mode
DISPLAY PAL -> This will put VDP in PAL Mode
DISPLAY NTSC -> This will put VDP in NTSC Mode

By mfeingol

Champion (293)

03-04-2016, 07:13

Awesome, thank you.

By NYYRIKKI

Enlighted (6033)

03-04-2016, 21:09

Victor wrote:

DISPLAY PAL -> This will put VDP in PAL Mode
DISPLAY NTSC -> This will put VDP in NTSC Mode

Actually this is not true... and the command format is very misleading.

You can not change color encoding with software, you can only select HZ-rate. When you use RGB it does not matter if the color encoding is NTSC or PAL. This is only important if you use composite output. How ever if you run this on European computer you can select between PAL or PAL60 and on Japanese computer you can select between B/W 50Hz and NTSC.

I now also created a small BASIC program that will make you 3 little programs more:

50Hz.COM will change to 50Hz mode
60Hz.COM will change to 60Hz mode
Hz.COM will toggle between 50Hz/60Hz mode

10 DEFINTA-Z:DIMD(7):FORI=0TO7:READD(I):NEXT
20 FORI=0TO2:IFITHENN$=HEX$(64+I*16):READD(2)
30 COPYDTON$+"Hz.COM":NEXT
40 DATA-6111,32511,750,-3209,-26157,-30402,-26157,201,758,-538

By AxelF

Champion (395)

03-04-2016, 21:31

NYYRIKKI wrote:

10 DEFINTA-Z:DIMD(7):FORI=0TO7:READD(I):NEXT
20 FORI=0TO2:IFITHENN$=HEX$(64+I*16):READD(2)
30 COPYDTON$+"Hz.COM":NEXT
40 DATA-6111,32511,750,-3209,-26157,-30402,-26157,201,758,-538

WOW that is awesome, very nice work...

By mfeingol

Champion (293)

04-04-2016, 03:35

Nyyrikki:

Works great, thank you.

By woody.cool

Supporter (9)

11-04-2016, 15:15

It works well, however, I've discovered a little something.

I have a Toshiba HX-10 (MSX1) and a Philips NMS-8250 (MSX2)

The listing does not work on the Tosh, I get a "Type mismatch" error on line 30
On the MSX2, it works fine and creates the 3x executables (HZ.COM, 50HZ.COM and 60HZ.COM) - great
All three executable work in MSX-DOS 2 and original MSX-DOS on the Philips (I copied them to an MSX-DOS 1 disk and booted it)
However, these tools do not work on the Tosh, when executed, the screen goes blank (still the default blank blue colour) and the machine crashed - only a power-cycle fixes it (it has not reset button)

Should these tools work on the MSX1?

By mars2000you

Enlighted (6437)

11-04-2016, 16:15

It can't work on a MSX1 because VDP frequency of MSX1 machines can't be modified, it's 'linked' to the used VDP (50Hz for European machines, 60Hz for Japanese, Korean, Russian and Brazilian machines).

By NYYRIKKI

Enlighted (6033)

11-04-2016, 18:43

As mars2000you already explained this is purely MSX2 stuff.

In MSX1 it goes like this:
TMS9918A outputs 60Hz NTSC
TMS9928A outputs 50Hz PAL
TMS9929A outputs 50Hz SECAM

Unfortunately you can't just desolder the VDP and change it to other model. It requires also changes outside VDP.

By Louthrax

Prophet (2436)

11-04-2016, 18:48

If I remember well, the VDP is socketed on the HX-10, so it's quite easy to replace. You'll then have a very simple cut & soldering operation on the LVA-510 chip, it's described here:
https://www.msx.org/forum/msx-talk/hardware/tint-issue-modified-toshiba-hx-10-lva510-related
That worked great for me (I really don't like 50Hz).

By Grauw

Ascended (10711)

11-04-2016, 19:06

Probably should also replace the BIOS then because some applications may still think it is 50 Hz (e.g. VGMPlay).