Some questions about Philips NMS8250

By Caspar

Supporter (7)

Аватар пользователя Caspar

13-03-2004, 17:40

Hello together

I have bought some time ago a Philips NMS8250 by ebay. Now I want to build it into a PC case. After I opened the MSX, some questions arose.

1. I saw that there must be additional RAM on it, but on the start screen I have only 128/128 displayed. How can I check how much additional RAM is it and is it OK?

2. There ist a 7MHz upgrade build in. I have a switch to use it and two other cable without a switch on it. For what are they?

3. There is a dip switch (SW101) in the middle of the master mainboard. What is the meaning of it?

3. I have a TFT Monitor with comp. video and s-video. How can I use them for my MSX? Maybe I need a RGB to S-Video converter like this one www.nexusuk.org/projects/rgb2svid/?

4. How can I use a PC-Keyboard on my MSX?

5. Where can I buy a cheap slot-expander? Have someone a slot-expander for me?

Thank you very much for yor answers!!!

Greetings
Chris

Для того, чтобы оставить комментарий, необходимо регистрация или !login

By flyguille

Prophet (3028)

Аватар пользователя flyguille

13-03-2004, 18:08

for know, how much memory are.... simply do that!..

Write it in direct basic command mde, NOT under LINE NUMBERS!!!

FOR PG=255 TO 0 STEP-1:OUT &HFE,PGTongueOKE &h8000,PG:NEXT:OUT &HFE, 255TongueRINT "AMOUNT MEMORY IN KBytes:"CryingPEEK(&h8000)+1)*16

NOTE: That work in a lot of cases, because in a lot of cases simply ignore BITS of the mapper registers, then got ghost repetition of the same RAM, one and other time.

A better way is do a basic program and save with SAVE"MEMCOUNT.BAS":

10 CLEAR: IFPEEK(&HF677) = 128 THEN POKE &HF677,&HC0: POKE&HC000,0: RUN"MEMCOUNT.BAS"
20 FOR PG=255 TO 0 STEP-1:OUT &HFE,PGTongueOKE &h8000,PG:NEXT
30 CO=0
40 FOR PG=0 TO 255
50 OUT &HFE,PG:X=PEEK(&H8000)
60 IF X<>PG THEN 80
70 CO=PG:NEXT
80 CO=(CO+1)*16
90 PRINT "AMOUNT MEMORY IN KBytes:";CO

THAT WORK IN ALL COMPUTERS.

By BiFi

Enlighted (4348)

Аватар пользователя BiFi

13-03-2004, 18:22

With Philips MSX2 computers there's a much easier method. It's definately NOT MSX standard though:

PRINT (INP(&HFF)XOR255+1)*16

will return the size of the memory mapped RAM as well.

By flyguille

Prophet (3028)

Аватар пользователя flyguille

13-03-2004, 18:33

BIFI , THAT RETURN THE COUNT, looking for the amount of BIT available on the mapper registers, that not work in all memory sizes... "only work if all bits of the mapper are used by RAM", and by example if got 128kb, not work, because the mapper can got 8, 5 or 4 bits and not 3.

By Arjan

Paladin (742)

Аватар пользователя Arjan

13-03-2004, 19:05

With Philips MSX2 computers there's a much easier method. It's definately NOT MSX standard though:

PRINT (INP(&HFF)XOR255+1)*16

will return the size of the memory mapped RAM as well.
change that to 'PRINT ((INP(&HFF)XOR255)+1)*16'
The + has a higher precedence than XOR.

By Caspar

Supporter (7)

Аватар пользователя Caspar

13-03-2004, 19:38

Thanks to all they helped me to know how much RAM my MSX has Wink

It has 256Kbyte!!!! LOL!

The first procedure of flyguille did not work. But his program work fine, thank you!

BiFi, when you follow the instruction of Arjan then this one works fine, thank you both!

Do you also know some answers to my other questions Question

Thanks a lot!
Chris

By flyguille

Prophet (3028)

Аватар пользователя flyguille

13-03-2004, 19:49

Thanks to all they helped me to know how much RAM my MSX has Wink

It has 256Kbyte!!!! LOL!

The first procedure of flyguille did not work. But his program work fine, thank you!

BiFi, when you follow the instruction of Arjan then this one works fine, thank you both!

Do you also know some answers to my other questions Question

Thanks a lot!
Chris

As, I say before, the first procedure work for a lot of cases, NOT ALL!!!! it is a hardware depends as the BIFI procedure...

My second procedure is for all msx2 computers procedure.

By Repair-Bas

Paragon (1125)

Аватар пользователя Repair-Bas

14-03-2004, 08:56

Hello

For the memory I have changed roms with a variable memory counter.
Then you can see in the intro screen how much memory you have.

The switch in the middle of the computer is the service switch. You have to you it with a service test cartridge. This switch switches the roms and the extern STC emulate the roms and then you can check the whole mother-board.

On 7 Mhz there are 4 for wires going extern the print. Two are for the switch and the other two are for the led. With this led you can see if 7 MHz is activ.

By Caspar

Supporter (7)

Аватар пользователя Caspar

14-03-2004, 10:11

Thanks a lot Repair-Bas for your input. Wink

For the questions about the slot-expander and the PC-Keyboard on a MSX I have found the web-site lpadial.aamsx.org/pages.HTM on the main site of the MSX Resource Center.

The question about the s-video and compsite-video was also answered, I think you know what I mean. :O

So thank you all and let the MSX alive!!

Cheers
Chris