Unknown model MSX TurboR with modem and serial

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بواسطة zeilemaker54

Champion (343)

صورة zeilemaker54

17-11-2015, 13:46

zeilemaker54 wrote:
mars2000you wrote:

If you boot while pressing the SHIFT to disable the dos2 rom, you'll be surprised : 59081 Bytes free instead of 25302 ... Very strange ...

Yes, that must be a bug somewhere in the ROMs. TXTTAB is not correctly initialized....

Ouch, that is due some very bad patching in the mainrom. Routine at 07D17H was patched with a interslot call to routine at 06000H in the serial ROM (which checks somewhat for the extra cartridge). But by patching the routine at 07D17H TXTTAB is not correctly initialized when the initialization of the disksystem is canceled (for example by pressing SHIFT). Clearly someone has taken too much sake at that time....

بواسطة zeilemaker54

Champion (343)

صورة zeilemaker54

17-11-2015, 16:27

zeilemaker54 wrote:
zeilemaker54 wrote:
mars2000you wrote:

If you boot while pressing the SHIFT to disable the dos2 rom, you'll be surprised : 59081 Bytes free instead of 25302 ... Very strange ...

Yes, that must be a bug somewhere in the ROMs. TXTTAB is not correctly initialized....

Ouch, that is due some very bad patching in the mainrom. Routine at 07D17H was patched with a interslot call to routine at 06000H in the serial ROM (which checks somewhat for the extra cartridge). But by patching the routine at 07D17H TXTTAB is not correctly initialized when the initialization of the disksystem is canceled (for example by pressing SHIFT). Clearly someone has taken too much sake at that time....

My conclusion was a bit too fast. If you use the NAI-2001 serial ROM, it all works correctly. It will mall function if you leave out the serial ROM.

بواسطة madscient

Master (193)

صورة madscient

17-11-2015, 17:26

zeilemaker54 wrote:

My conclusion was a bit too fast. If you use the NAI-2001 serial ROM, it all works correctly. It will mall function if you leave out the serial ROM.

NIA-2001 serial and modem features might not complies MSX standard.
At least, MSX-BASIC extension is not implemented.
I'm guessing NIA serial and modem designs were diverted from CAPTAIN Multi Station.

بواسطة mtn

Champion (269)

صورة mtn

17-11-2015, 19:59

بواسطة zeilemaker54

Champion (343)

صورة zeilemaker54

17-11-2015, 21:11

madscient wrote:

NIA-2001 serial and modem features might not complies MSX standard.
At least, MSX-BASIC extension is not implemented.

MSX serial is completely standard (version 1 hardware, I/O ports 080H-087H), latest code base. No missing BASIC extension. What features are you missing ?

بواسطة Piter Punk

Master (228)

صورة Piter Punk

18-11-2015, 00:45

zeilemaker54 wrote:
madscient wrote:

NIA-2001 serial and modem features might not complies MSX standard.
At least, MSX-BASIC extension is not implemented.

MSX serial is completely standard (version 1 hardware, I/O ports 080H-087H), latest code base. No missing BASIC extension. What features are you missing ?

CALL COMINI, CALL COMTERM and other BASIC commands works OK. But I didn't try any "modem" commands, and I don't know if the connector in front of this machine is another serial port.

بواسطة mars2000you

Enlighted (6346)

صورة mars2000you

18-11-2015, 13:24

I've noticed that using of the AUCNET cartridge has as effect to change some parameters in the RTC :

#1E  01 replaced by 00 = screen 1 replaced by screen 0

#1F 0D replaced by 08
#20 01 replaced by 02 = width 29 replaced by width 40

# 22 04 replaced by 00 = background color
# 23 07 replaced by 00 = border color

# 25 00 replaced by 03  = beep high tone, very low volume replaced by high tone, high volume

# 28 (27 in openMSX) 00 replaced by 04 (unusual value for the choice title, password, prompt in the RTC !)

I've also found a very simple way to bypass the screen inviting to insert the AUCNET cartridge : you just need to patch the RS232C rom at offset 2004 by replacing C9 by 00. No more need to press 6 keys at the same time to access to the MSX-BASIC screen !!! Wink

It also means that the RS232C rom can always be correctly mapped for the config in blueMSX. No more risk to get excessive free memory for BASIC if you boot while pressing the SHIFT key to disable the DOS2 rom !

بواسطة l_oliveira

Hero (534)

صورة l_oliveira

18-11-2015, 16:34

Just a comment of mine... There are MSX2+ units with JIS level 1 fonts (SANYO MSX2+ units for example). Those have only 128KB of kanjirom fonts.

I believe the toshiba MASKROM is the kanji font.

I had discussions with the openMSX people about the kanjirom font because what's written on the ROM chip is *NOT* encoded the same way as software dumps store the data.

Due to how kanji works (radicals and particles stuff) any kanji character to be formed is dealt as a set of four tiles. On the real ROM chip the upper left and right corners are stored on the first half of the rom and the bottom left and right corners are stored on the secodn half of the rom. All grouped together. When read through software by the kanjirom I/O ports the data is reordered in a interleaved way, which gives you a complete character every time (by the hardware mechanism). So the dump of the rom chip will never match what is read from the ROM itself.

Using the S1990 mechanism of dumping will give you a raw dump of the chip, not the same data you would get reading through the I/O port. Just trying to explain why the kanji font looks different between dumps.

بواسطة madscient

Master (193)

صورة madscient

18-11-2015, 18:40

Piter Punk wrote:
zeilemaker54 wrote:
madscient wrote:

NIA-2001 serial and modem features might not complies MSX standard.
At least, MSX-BASIC extension is not implemented.

MSX serial is completely standard (version 1 hardware, I/O ports 080H-087H), latest code base. No missing BASIC extension. What features are you missing ?

CALL COMINI, CALL COMTERM and other BASIC commands works OK. But I didn't try any "modem" commands, and I don't know if the connector in front of this machine is another serial port.

Oh, It's my misunderstanding...
I've found MSX-SERIAL commands and BIOS too...

BASIC commands of MSX-MODEM contains all MSX-SERIAL commands, and some MSX-MODEM-specific commands, such as "CALL NETINI".

In the case of the computer which have both feature, multiple serial channels are available with _COMINI.

بواسطة l_oliveira

Hero (534)

صورة l_oliveira

18-11-2015, 18:55

on the motherboard pictures it's possible to see the NEC chipset clones of Intel UART chips:
(microPD)upD71054C, upD71051C (two, likely one is used for the modem perhaps?) and HD75188/HD75189 (RS232 voltage level converters) so indeed there's a full complete RS232 C present and likely that's what basic commands are interacting with.

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