Sanyo MBC-XXXX CP/M models

stefano
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Sanyo MBC-XXXX CP/M models

Post by stefano »

Sanyo had its own CP/M computers series, for what I could find digging around, 4 different disk formats were used:

Sanyo MBC-1000/1100/1150 - DSDD 48 tpi 5.25"
the interface card for the EFD860F allowed 2 additional 8" external drives

Sanyo MBC-1200/1250 - DSDD 96 tpi 5.25", 80 tracks (two 4.0 MHz Z80A CPUs and 640 kB disk drives, high resolution graphics)
The MBC-200, MBC-225 (and probably also the MBC-250) were equivalent models for the western markets.

Also the MBC-1160 had the same disk format, I don't know if it had the same graphics capability.


Sanyo MBC-2000 (8085 CPU) - SSDD 96 tpi 5.25"


Sanyo MBC-3000, 8" - 26 sectors/track

(A good timeline is here: https://moainet.org/sadoru/pc/sanyo.html )

I could get cpmtools correctly edit the existing system disk images for the first (EDIT: three) machine groups:

Code: Select all


# SAN1 Sanyo MBC-1000/1100/1150 - DSDD 48 tpi 5.25" - 256 x 16
diskdef san1
seclen 256
tracks 80
sectrk 16
blocksize 2048
maxdir 64
skew 3
boottrk 2
os 2.2
end

# Sanyo MBC-1200/1250 - DSDD 96 tpi 5.25" - 256 x 16
# Probably valid also for MBC-250/225/200
# 256 byte sector, 1-16, 1:1, 96 tpi

diskdef san2
  seclen 256
#  tracks 160
  sectrk 16
  blocksize 4096
  maxdir 128
  skew 3
   tracks 80
   heads 2
   sides outback
  boottrk 4
  os 2.2
end


# Sanyo MBC-2000 - SSDD 96 tpi 5.25" - 256 x 16
diskdef san3
  seclen 256
  tracks 80
  sectrk 16
  blocksize 2048
  maxdir 64
  skew 5
  boottrk 4
  os 2.2
end

The MBC-200 is emulated by MAME, which is great because of the graphics capabilities.
By the way I'm not sure the current appmake implementation is able to generate a a valid IMD image for the MBC-1200 series, as you can see I tricked CPMTOOLS by suggesting to work on a single side disk image.
Reasonably, MAME complains when it meets a 160 tracks disk. Sadly it is not currently configured to accept a RAW format on the MBC-200 system type.
I'm going to test the RAW generated image by shuffling the sectors with IMD and see if MAME likes it in that way.
I noticed already that MAME seems to be reluctant to seek the second drive. Accessing to the virtual units E: and F: seems to help.
Moreover, it looks like a 40 tracks format is allowed in read-ony mode (CP/M sometimes fires out a warning about it).
In Australia it was part of a business line, iirc IMS.
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dom
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Re: Sanyo MBC-XXXX CP/M models

Post by dom »

stefano wrote: Sun Mar 26, 2023 2:15 pmBy the way I'm not sure the current appmake implementation is able to generate a a valid IMD image for the MBC-1200 series, as you can see I tricked CPMTOOLS by suggesting to work on a single side disk image.
The skew handling in appmake is fairly "funky" - is that the problem or is it something else?
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Re: Sanyo MBC-XXXX CP/M models

Post by stefano »

> The skew handling in appmake is fairly "funky" - is that the problem or is it something else?

I suppose so, I'll try to focus on it, then.

My best guess for a valid appmake configuration is:

Code: Select all

static disc_spec mbc1200_spec = {
    .name = "MBC-1200",
    .sectors_per_track = 16,
    .tracks = 80,
    .sides = 2,
    .sector_size = 256,
    .gap3_length = 0x17,
    .filler_byte = 0xe5,
    .boottracks = 4,
    .directory_entries = 128,
    .extent_size = 4096,
    .byte_size_extents = 1,
    .first_sector_offset = 0,
    .alternate_sides = 1,
    .has_skew = 1,
    .skew_tab = { 0,3,6,9,12,15,2,5,8,11,14,1,4,7,10,13 }
//    .skew_tab = { 0,1,6,7,12,13,18,19,24,25,30,31,4,5,10,11,16,17,22,23,28,29,2,3,8,9,14,15,20,21,26,27 }
};

On CP/M, the skew table deals with the larger sector size in this way:
MBC-200.png
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dom
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Re: Sanyo MBC-XXXX CP/M models

Post by dom »

I use the following to debug disc spec errors:

1. In disc_create() change the #if 0 to #if 1 - this will fill the disc with track/sector/head
2. In cpm_write_file() comment out this memcpy: memcpy(h->image + offset, data, len);

This means in mame you can then stick a breakpoint at 0x100, dump the memory and see what sectors have been loaded when you attempt to launch the command.
stefano
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Re: Sanyo MBC-XXXX CP/M models

Post by stefano »

Good, I'm currently refining the way cpm_write_file() feeds the directory extents, under some circumstance it fools cpmtools (and probably some of the existing CP/M implementations) making it transfer bigger files than real.
The bigger problem happens when an extra empty directory entry is created, but I'm trying to avoid the extra size on the record counter (byte 15) as well.
It should make the generated RAW images closer to the results obtained with cpmtools and help in comparing the interleaved disk images.

EDIT: I decided to patch appmake gradually, the filesize bug should be fixed now. Please alert me in case I broke something !
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Re: Sanyo MBC-XXXX CP/M models

Post by stefano »

I finally made it !
The skew implementation was sufficient (but I'm using my current test configuration to clean it up a little) .
I was missing a sector count offset, a different speed rate, and the fact that MAME fails in reading drive B !
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Re: Sanyo MBC-XXXX CP/M models

Post by stefano »

The MBC-3000 is not an emulated target, but I could extract the files with cpmtools.
It was a 77 tracks 8" disk format with a peculiarity described in the cpmtools/libdsk tutorials: a track 0:0 with halved density.
I'm telling just to suggest whoever is interested in such topics a new option for cpmtools or similar, the only cases I'm aware of just need the first track in side 0 to be considered halved.

EDIT: there is a way actually to do it on cpmtools, considering that on the MBC-3000 the first sector can be fattened by doubling it, we can put extra 128*26 bytes (=3328).

Code: Select all


# Sanyo MBC-3000 - DSDD 8" - 256 x 26
diskdef san4
  seclen 256
   heads 2
   sides outback
  sectrk 26
  blocksize 4096
  maxdir 128
  skew 6
  boottrk 4
  os 2.2
  offset 3328
end

stefano
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Re: Sanyo MBC-XXXX CP/M models

Post by stefano »

One more interesting hint: the only graphics models are the ones in the MBC-200/MBC-1200 family.
They were delivered with a special, extended BASIC (SBASIC-3) which included graphics instructions (but TIME was missing, it was available on the MBC-2000 and MBC-3000 models only).
The Sanyo BASIC was not accessing the graphics mode directly, it relied on terminal ESC sequences, presumably provided by the BIOS.

I haven't the manuals but basing on this ancient post, it looks like the terminal was poorly documented:
https://dflund.se/~pi/cpm/files/ftp.may ... rn.doc.txt


I could track something redirecting the console output of a generic cp/m emulator:

Code: Select all

    "Reset from ESC" (exit from graphics mode if the ESC sequence was interrupted, do nothing if in text mode):
    1b 54
    0d 0a 1b 54 

    Draw a pixel (coordinates are little endian)
    Reset a pixel:  change to (ESC) R
    1b 54
        1b 53               <- (ESC) S
            YY YY XX XX
    0d 0a 1b 54


    Draw a line (X0,Y0)-(X1,Y1)
    1b 54
        1b 50 30               <- (ESC) P0
            Y0 Y0 X0 X0
            Y1 Y1 X1 X1
    0d 0a 1b 54
 
stefano
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Re: Sanyo MBC-XXXX CP/M models

Post by stefano »

Thus, including cpm.h and shortcutting to BIOS, we can try to draw a line from (5,5) to (50,50):

Code: Select all


  bios(BIOS_CONOUT,0x1b,0);
  bios(BIOS_CONOUT,0x54,0);

  bios(BIOS_CONOUT,0x1b,0);
  bios(BIOS_CONOUT,0x50,0);
  bios(BIOS_CONOUT,0x30,0);

  bios(BIOS_CONOUT,0,0);
  bios(BIOS_CONOUT,5,0);

  bios(BIOS_CONOUT,0,0);
  bios(BIOS_CONOUT,5,0);

  bios(BIOS_CONOUT,0,0);
  bios(BIOS_CONOUT,50,0);

  bios(BIOS_CONOUT,0,0);
  bios(BIOS_CONOUT,50,0);


  bios(BIOS_CONOUT,0x0d,0);
  bios(BIOS_CONOUT,0x0a,0);

  bios(BIOS_CONOUT,0x1b,0);
  bios(BIOS_CONOUT,0x54,0);

mbc200-draw.png
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stefano
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Re: Sanyo MBC-XXXX CP/M models

Post by stefano »

Update: the console ESC commands are simpler, the CR/LF is pointless, I haven't fully understood why the Sanyo Basic mixes them with the reset sequence, probably it's a side effect of a generic "console reset" command.
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Re: Sanyo MBC-XXXX CP/M models

Post by stefano »

Minimal set of graphics functions for the MBC-1200:

Code: Select all

#include <cpm.h>

int x,y;


void line (int x0,int y0,int x1,int y1) {
  bios(BIOS_CONOUT,27,0);
  bios(BIOS_CONOUT,'P',0);
  bios(BIOS_CONOUT,'0',0);

  bios(BIOS_CONOUT,y0>>8,0);
  bios(BIOS_CONOUT,y0,0);

  bios(BIOS_CONOUT,x0>>8,0);
  bios(BIOS_CONOUT,x0,0);

  bios(BIOS_CONOUT,y1>>8,0);
  bios(BIOS_CONOUT,y1,0);

  bios(BIOS_CONOUT,x1>>8,0);
  bios(BIOS_CONOUT,x1,0);
}


void line_reset (int x0,int y0,int x1,int y1) {
  bios(BIOS_CONOUT,27,0);
  bios(BIOS_CONOUT,'P',0);
  bios(BIOS_CONOUT,'1',0);

  bios(BIOS_CONOUT,y0>>8,0);
  bios(BIOS_CONOUT,y0,0);

  bios(BIOS_CONOUT,x0>>8,0);
  bios(BIOS_CONOUT,x0,0);

  bios(BIOS_CONOUT,y1>>8,0);
  bios(BIOS_CONOUT,y1,0);

  bios(BIOS_CONOUT,x1>>8,0);
  bios(BIOS_CONOUT,x1,0);
}


void pset (int x, int y) {
  bios(BIOS_CONOUT,27,0);
  bios(BIOS_CONOUT,'S',0);

  bios(BIOS_CONOUT,y>>8,0);
  bios(BIOS_CONOUT,y,0);

  bios(BIOS_CONOUT,x>>8,0);
  bios(BIOS_CONOUT,x,0);
}

void preset (int x, int y) {
  bios(BIOS_CONOUT,27,0);
  bios(BIOS_CONOUT,'R',0);

  bios(BIOS_CONOUT,y>>8,0);
  bios(BIOS_CONOUT,y,0);

  bios(BIOS_CONOUT,x>>8,0);
  bios(BIOS_CONOUT,x,0);
}


void init () {
  bios(BIOS_CONOUT,27,0);
  bios(BIOS_CONOUT,'T',0);
}


void main()
{
  init ();
  for (y=0; y<400;y++) {
    for (x=0; x<640;x++) {
		pset (x,y);
	}
  }
}

stefano
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Re: Sanyo MBC-XXXX CP/M models

Post by stefano »

Easy edit of mandel.c by using the functions above.
I set video boundaries to 640, 399 and replaced clg() with init() and plot(x,y) with pset(x,y).
mandel.png
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stefano
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Re: Sanyo MBC-XXXX CP/M models

Post by stefano »

I tried to squeeze out a little more of information on the terminal by disassembling the ROM of the secondary CPU.
I also noticed that all the Sanyo have a common set graphics symbols (not all of them, just something, but the full/empty ball ones are more than enough to run a personalized version of "Othello" :)

This is a first draft of the valid codes, plus the bit of information about the way they work I could discover so far:


$07 -> BEL
$08 -> BS backspace, does NOT touch the right side of the text line
$09 -> TAB
$0A -> LF
$0D -> CR
$1A -> CLS

$1B (ESC)

ESC "Q"
ESC "K"
ESC "A" <<<--- 40 lines mode (not all the text attributes are supported, slow scroll)
ESC "F"
ESC "C" YY XX ?
ESC "=" 32+Y 32+X -> change current text cursor/position (considering 0,0 as top-left position)
ESC "S" YY XX -> set pixel
ESC "R" YY XX -> reset pixel
ESC "T" -> clear text up to end of the current line
ESC "I" -> insert line at the current cursor position (scroll down the remaining text)
ESC "B" -> delete line at the current cursor position (scroll up the remaining text)
ESC "L" <length> #..# ---> Upload custom routine at $2000, lenght follows (MSB/LSB), max 3960 bytes
ESC "JP" ---> Jump to custom routine at $2000
ESC "G"
ESC "M" <<<--- 33 lines mode (default)
ESC "D" -> disable..?
ESC "E" -> enable..?
ESC "P0" YY XX YY XX
ESC "P1" YY XX YY XX
ESC "HR" -> get dump data from screen ($7D00 bytes)
ESC "HT" n nnnn -> dump data to screen ($7D00 bytes)
ESC "N" -> Invert the current picture
ESC "?" -> reset terminal (cold reset)
ESC "t" 0 -> attributes off
ESC "t" 2 -> underline
ESC "t" 4 -> Inverse on
ESC "t" 6 -> Inverse on "+ underline"
ESC "t" 8 -> line on top of the the text

othello.png
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cborn
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Re: Sanyo MBC-XXXX CP/M models

Post by cborn »

do you know something about datapoint?
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Re: Sanyo MBC-XXXX CP/M models

Post by stefano »

No, but I can try to help. Are you referring to a specific computer model ?

EDIT: ..or perhaps you are referring to the ancient terminal?
https://bitsavers.org/pdf/datapoint/330 ... ctions.pdf
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Re: Sanyo MBC-XXXX CP/M models

Post by stefano »

Direct communtication with the video CPU, skipping the BIOS:

void mbc_sendchar(int chr) __z88dk_fastcall
{

__asm

send_rdy:
in a,($ea)
and $80
jr z,send_rdy

ld a,l
out ($e8),a

__endasm;

}
cborn
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Re: Sanyo MBC-XXXX CP/M models

Post by cborn »

stefano wrote: Thu Apr 06, 2023 8:43 am No, but I can try to help. Are you referring to a specific computer model ?

EDIT: ..or perhaps you are referring to the ancient terminal?
https://bitsavers.org/pdf/datapoint/330 ... ctions.pdf
the ancient model 1550 indeed, this is the 3300 already?
a pcb seams out of place. its a "monster" with a Z80 ;)
stefano
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Re: Sanyo MBC-XXXX CP/M models

Post by stefano »

https://bitsavers.org/pdf/datapoint/1500/
I don't think a CP/M boot disk image is available, but it existed:
http://www.bitsavers.org/pdf/datapoint/ ... 200_29.pdf
The problem is that LifeBoat was a terrible sw distributor, (they held the BDS C under contract strongly limiting it).
stefano
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Re: Sanyo MBC-XXXX CP/M models

Post by stefano »

The BIOS portion related to the console output is slightly more complex when loaded from disk than the one used by firmware for the "boot error" message, my guess is that the communication to the video CPU can be summarized in this way:

Code: Select all

void mbc_sendchar(int chr)  __z88dk_fastcall
{
__asm

send_rdy:
	in a,($ea)
	and $80
	jr z,send_rdy
	
	in a,($e9)
	and $fe
	out($e9),a
	
	ld a,l
	out ($e8),a

__endasm;
}

int mbc_getword()
{
__asm

rcv_rdy:
	in a,($e8)
	ld b,0
	call rcv_sub
	ld hl,-1		; error
	ret z
	
	in a,($e8)
	or $80
	ld h,a          ; MSB

	ld b,4
	call rcv_sub
	jr nz,no_err
	ld hl,-1		; error
	ret

no_err:
	in a,($e8)
	ld l,a          ; LSB
	ret


rcv_sub:
	in a,($ea)
	bit 5,a
	ret nz
	djnz rcv_sub
	xor a
	ret

__endasm;
}

.. but they're still totally untested !
stefano
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Re: Sanyo MBC-XXXX CP/M models

Post by stefano »

Now things get funny.

I found the entry points to upload and run code on the second CPU (I'm keeping the ESC list above updated).

Code: Select all

		mbc_sendchar(27);
		mbc_sendchar('L');
		mbc_sendchar(0);
		mbc_sendchar(15);
			mbc_sendchar(0xC5);  // PUSH BC
			mbc_sendchar(0x21);  // ld hl, FONT and previous $FF filler
			mbc_sendchar(0xAE);
			mbc_sendchar(0x0A);
			mbc_sendchar(0xED);  // ld de,($3FA6)  ..(VRAM)
			mbc_sendchar(0x5B);
			mbc_sendchar(0xA6);
			mbc_sendchar(0x3F);
			mbc_sendchar(0x01);  // ld bc,$1552
			mbc_sendchar(0x52);
			mbc_sendchar(0x15);
			mbc_sendchar(0xED);  // ldir
			mbc_sendchar(0xB0);
			mbc_sendchar(0xC1);  // POP BC
			mbc_sendchar(0xC9);  // RET
		

		printf("%cJP",27);

copyfont.png


For reference, here's the "invert picture" function in ROM

Code: Select all


; Routine at 1216
L04C0:
  LD DE,$7D00
  LD HL,($3FA6)
L04C0_0:
  LD A,(HL)
  CPL
  LD (HL),A
  CALL INCHL_DECDE
  JR NZ,L04C0_0
  RET

; Routine at 1231
INCHL_DECDE:
  INC HL
  LD A,H
  OR $80
  LD H,A
  DEC DE
  LD A,D
  OR E
  RET
  
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stefano
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Re: Sanyo MBC-XXXX CP/M models

Post by stefano »

..the ROM disassembly of the video section

https://github.com/z88dk/techdocs/blob/ ... 200vid.asm
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Re: Sanyo MBC-XXXX CP/M models

Post by stefano »

The DataPoint 1500. I looked at the DOS.H diskette dumps after having converted them into RAW with IMDU.
It seems to be possible to decode it to extract the files or track down the format specs, but it's probably pointless to work on it without a working emulator.
Files could be segmented, the file extents were marked on the first sector byte, probably also the file length etc. follows.

The formatting process stored a useful marker, which is perfectly readable at the beginning of any unused track:
" TRACK: 0065 SECTOR: 0 DATAPOINT CORPORATION'S DISK OPERATING SYSTEM DOS.H VER 2.6 - 25FEB81 10:20"
It helps in understanding the diskette format, it's probably split into 77 tracks, 13 logical sectors of 256 bytes each (the physical sectors .

The directory seems to be a simple list of the filenames with the file position on top (4 bytes, big endian).


The filespec at command line was similar to the TRS80 one, e.g. FILE/TXT:D1
Interesting abstracts: "..now supports double density diskette operation on the 1401/1403/1404 diskette controllers on 1550"
http://bitsavers.informatik.uni-stuttga ... _Jul80.pdf

"..system for the Datapoint 1500 series processors, supporting the DOS.C and DOS.G diskette file structure, and the DOS.D 9320 disk file structure. One to four 9310/9320 disks are supported on 64K+ machines."
The 9320 cartridge disk system was a ten-megabyte disk-and-drive unit contained in a desk-top cabinet. It had a 256-byte buffer (one sector).
Two switches were present on the front panel of the disk unit: RUN/LOAD and WRITE PROTECT ON/OFF.


The online documentation is for a newer version of DOS.H (2.7):
"SOFTWARE CANCELLED BY THIS RELEASE: DOS.H 2,6 & DOS.H 2.6.1
Disk operating system for the Datapoint 1500 series processors, supporting the DOS.C and DOS.G diskette file structure, and the 4 logical drive, 2 logical drive, and 1 logical drive 9320 disk format. One to four 9310/9320 disks are supported on 64K+ machines. Supports one to two 154X or 1402 diskette controllers on 1500 processors, and one to four 1401/1403/1404 diskette controllers or one to two 154X/1402 diskette controllers on 1550 processors."


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stefano
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Re: Sanyo MBC-XXXX CP/M models

Post by stefano »

:O ... The MBC-200/1200 had more than a full 640x400 graphics pages !
And it was done only to provide smooth text scrolling !!

Code: Select all

  LD HL,($3FA8)      ; Screen start address for scrolling
  POP AF
  PUSH AF
  LD DE,80
DO_SCROLL_1:
  ADD HL,DE
  DEC A
  JR NZ,DO_SCROLL_1
  LD ($3FA8),HL
  LD A,12            ; Display Start Address (High)
  OUT ($B0),A
  LD A,H
  OUT ($B1),A
  LD A,13            ; Display Start Address (Low)
  OUT ($B0),A
  LD A,L
  OUT ($B1),A
  POP AF
  LD DE,80*4
  LD HL,($3FA6)      ; VIDEO MEMORY
DO_SCROLL_2:
  ADD HL,DE
  DEC A
  JR NZ,DO_SCROLL_2

This is embarassing, there is a relevant number different ways to use the second CPU board.. most of which excludes the other ones and require a lot of code.
The bit-banging sound runs on the video board as well:

Code: Select all

  IN A,($72)
  OR $10
  OUT ($72),A
  CALL DELAY_PERIOD
  IN A,($72)
  AND $EF
  OUT ($72),A
  CALL DELAY_PERIOD

Moreover, considering that different firmware versions existed, I think I should first upload and run a probe routine to determine the real position of the display functions before calling them.
To avoid hardware scrolling and upload part of the graphics library on the second memory page is crazy but tempting :D
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Re: Sanyo MBC-XXXX CP/M models

Post by stefano »

I'm afraid I reached the current emulator limits.
The talkback channel is not active yet, and the few commands relying on it simply hang up.
This limits the choices for a driver, I can still throw code and data in the video board, but, in example I can't test the current value of a pixel.. well the drivers running on the second CPU still can do it, there still plenty of space for a bit of magic.
I'll try to improve MESS, I should be able at least to make it enable the second drive correctly.
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Re: Sanyo MBC-XXXX CP/M models

Post by stefano »

A first PR was accepted, now the MBC-200 emulation works right with the floppy drive selector.
This allows accessing to the virtual drive F:, which enables a different DPB table for reading the older SANYO disk drive format (MBC-1000/MBC-1100).
40trk.png
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