¿Can be switched to 60hz an MSX1 PAL?

Prophet (3189)

09-02-2014, 20:48

Hi, I've recentrly bought a MSX1 computer HB75P. I was surprised when I inserted megaflashrom scc+ sd with several roms loaded, has started multiboot menu to select the rom and de botton menu (where yo choose hz) is not accesible presing Tab or Fire 2. All games starts at 50hz. The same menu loads correctly on mi 2+ and I can change freely 50/60hz.

Are the PAL MSX1 locked to 50hz?

Thanks.

By hit9918

Prophet (2926)

09-02-2014, 20:59

The menu is ok. The MSX1 VDP is hardwired, cannot change Hz.

By Huey

Prophet (2693)

09-02-2014, 22:09

It can't be changed on MSX1 from 50 to 60hz by software.

Some MSX1 models have the VDP on a socket. Z80st once did replace such a VDP with a 60hz version. I still have to try it myself. I have all the needed stuff (Toshiba MSX1 + 60hz VDP + cooling sink) but I didn't make the time yet to try it.

By AxelStone

Prophet (3189)

10-02-2014, 13:44

I've seen the tutorial, thanks. As anybody knows if HB75P has the VDP in a slot too?

By Manuel

Ascended (19198)

10-02-2014, 14:26

Open the case and take a look?

By Capitan_Goto

Master (168)

10-02-2014, 16:36

http://bilgisayarlarim.com/Sony/HB-75P/

Not sure, but it seems that yes...it´s socked...

By Lord_Zett

Paladin (807)

10-02-2014, 16:46

no, its the one under the metal plate

By AxelStone

Prophet (3189)

10-02-2014, 19:24

Lord_Zett wrote:

no, its the one under the metal plate

Really bad news

Apart from toshiba-hx10, someone knows other models with de 9929 chip socked in a slot?

By l_oliveira

Hero (534)

15-02-2014, 02:11

You don't want to replace the VDP to get 60hz. You will get 60hz with wrong colors.

By AxelStone

Prophet (3189)

10-05-2014, 12:24

Hi everyone, I can confirm that the operation has gone right. I've replaced the integrated TMS9929 (PAL) for TMS9928 (NTSC) and now I've a HB75P working at 60hz all time. There is no color problem or any other related trouble, yo'll get simply a 60hz MSX1

By l_oliveira

Hero (534)

10-05-2014, 15:18

AxelStone wrote:

You will get different hues on the colors. The colors are there but they are wrong. (red will be slightly pink for example)

Because the PAL video chip has different voltage levels for the colors.

Now, if you don't mind wrong colors, good for you.