MacroSystem DraCo emulation

[Toni Wilen]

Yes because it is not full 128k. I padded it with zeros before taking checksums. (mentioned previously in this thread, v1.3 also had zero padding). I guess it was originally software loaded ROM update that was officially released by MacroSystem (boot ROM menu has option to load new boot ROM and reboot). Replacement is easy because both KS and boot ROM are copied to RAM, then patched and then remapped with MMU.

[Toni Wilen]

I also checked Casablanca (again), it is quite similar in parts (same SCSI, same SuperIO, boot ROM is mostly similar too) but video part is totally different. None of chips on video PCB have anything to do with (S)VGA. It has digital video decoder/encoder/DAC/ADC/DRAM/FIFO/Audio DAC and lots of CPLDs.

Which means there is very little chance to get even boot ROM image visible. Unless some specs are available.

[gulliver]

Originally Posted by Toni Wilen

I also checked Casablanca (again), it is quite similar in parts (same SCSI, same SuperIO, boot ROM is mostly similar too) but video part is totally different. None of chips on video PCB have anything to do with (S)VGA. It has digital video decoder/encoder/DAC/ADC/DRAM/FIFO/Audio DAC and lots of CPLDs.

Which means there is very little chance to get even boot ROM image visible. Unless some specs are available.

After designing the DraCo what MacroSystem did was to cut down production costs on it by removing hardware extensions they did not needed for the task at hand.

In the case of the video, its interface is done by pumping out video frames directly to YC/composite from the DraCoMotion. The video capture sections of the DracoMotion can be resumed as follows:

1) A realtime digitizer/framegrabber
2) A fast JPEG compressor/decompressor
3) A framebuffer
4) A Genlock and chroma keyer (Blue Box)

In the case of the Casablanca, sections 3) and 4) are reused for video output. This is a clever components and cost reduction strategy, but of course, it limits their output to YC/composite which is just fine for this purpose.

In the DEVELOPMENT/VLABMOTION directory you will find associated information regarding this subject.

[ShK]

Originally Posted by Toni Wilen

Keyboard implemented (from x86box with some hacks, DraCo boot ROM uses commands that even x86box does not implement)

Keyboard is "directly" connected, bypasses all input panel remappings. Some keys causes DraCo to report illegal key alert (why is that unrecoverable? Stupid thing), didn't debug that yet.

Is there way to prevent double letters in one key press?

[Toni Wilen]

Originally Posted by ShK

Is there way to prevent double letters in one key press?

Does not happen here.

EDIT: same without startup-sequence? Older version worked? (if you tried them)

EDIT2: Odd, that happens when in WB string requesters but nowhere else.

[ShK]

It seemed to fixed after I deleted envarc:sys/locale.prefs

e: and it came back. I thought it was something what c:iprefs does, but issue seems to vary between double letters and keyboard not working at all. Sometimes double letters even without startup-sequence.

[Toni Wilen]

Floppy drive state is now reported correctly (no more DF0:??? in WB)
Floppy drive reads are now implemented (PIO!) but driver does not seem to accept the returned data. I still have no idea how Amiga formatted floppies can work with PC controller..
RTC unique serial number emulated. Currently returns 451 (DraCo serial number is ID + checksum byte concatenated. ID = 1. Checksum = 0xC3 = 0x1C3 = 451). Edit NVRAM (byte offsets 1 to 6, first byte is at offset 0) if you want other serial numbers, checksum is automatically calculated.

[Docent]

Originally Posted by Toni Wilen

Floppy drive state is now reported correctly (no more DF0:??? in WB)
Floppy drive reads are now implemented (PIO!) but driver does not seem to accept the returned data. I still have no idea how Amiga formatted floppies can work with PC controller..

You should probably provide data in the same format as pc controller. The trick is, they used amiga fast file system mounted on top of their trackdisk device that read pc floppies - the pc format used is 10 sectors of 1024 bytes each.

I know this because in the nineties I did the Polish localization of Casablanca for official Casablanka distributor in Poland (via reverse engineering floppy format and their software) and a couple of comercially sold font sets for Casablanka.
Hd floppy in my amiga did all the duplication

[Toni Wilen]

Originally Posted by Docent

You should probably provide data in the same format as pc controller. The trick is, they used amiga fast file system mounted on top of their trackdisk device that read pc floppies - the pc format used is 10 sectors of 1024 bytes each.

I know this because in the nineties I did the Polish localization of Casablanca for official Casablanka distributor in Poland (via reverse engineering floppy format and their software) and a couple of comercially sold font sets for Casablanka.
Hd floppy in my amiga did all the duplication

This is not Casablanca, it uses different disk format. DraCo seems to use normal 512 byte tracks and does support both PC and Amiga formatted disks (still not sure how).

[gulliver]

A couple of hopeful hints that may help in finding out the floppy support issue on the DraCo.

The DraCo natively supports its own format which is not Amiga compatible. It can also access Amiga floppies in read only mode, but never write to them. Also once a format is chosen, it cannot be changed for another, for that, you must reboot.

Whenever I used my DraCos with their own custom floppy format, they performed reasonably well considering the floppy disk limitations. But whenever I used an Amiga floppy and wanted to read from it, my DraCos came to a painful crawl, it looked like I was using a slow 7 Mhz 68000 instead of a fast 68060. Multitasking was at its knees.

My humble take about this is that the Amiga floppy disk format is read using an incredibly intense decoding procedure which takes a heavy toll on the CPU, unlike other formats. It may probably resemble in some related way how some PC software today manages to read Amiga floppies using only unmodified standard PC floppy drive units.

It is also worth remembering that the DraCo does not use trackdisk.device, but its own dracodisk.device for this purpose.

And just for the sake of completion, here is what I have about the supported DraCo floppy formats:

The "DraCoFloppy" program

Turns on and off of the floppy disk drives. By turning off
floppy drives, the boot process is accelerated because
the associated test is omitted.

It also allows changing the format of the currently
inserted disk. The floppy disk drive in a DraCo can read
and write different formats. However, when a disk format is
chosen, the floppy disk drive continues to use that format
every time. If the user chooses to change the floppy format,
a system reset will be required.

The following are the floppy formats a DraCo can be easily
configured to use:

1 = 720 KB (Amiga, DraCo, PC)
2 = 800 KB (Amiga, DraCo)
3 = 880 KB (DraCo)
4 = 960 KB (DraCo)
5 = 1.44 MB (Amiga, DraCo, PC) requires a high density
floppy disk drive (HD)
6 = 1.76 MB (Amiga, DraCo) requires a high density floppy
disk drive (HD)

Due to the nature of the Amiga floppy format, it imposes a
heavy burden on the resources of the DraCo when it is
being read. Besides that, no write operations whatsoever
can be performed on the floppy whilst using this specific
format, as it becomes a read-only medium.

The Amiga via special mountlist entries can also read and
write DraCo floppies without problems. This should be the
normal way to exchange small amounts of data between the
Amiga and the DraCo. For the corresponding mountlist
entries, see the Storage/DOSDrivers directory which should
contain the following floppy specific mountlists:

DRDD is for reading and writting a double density DraCo
floppy format (720KB)
DRHD is for reading and wrritting a high density DraCo
floppy format (1.44MB)
PCA is for reading and writing a PC floppy format in drive
DFO: (Filename length limitations apply in PC compatible
mode. Maximum 8 characters with a "." plus a 3 character
name extension).
PCB is for reading and writing a PC floppy format in drive
DF1: (Filename length limitations apply in PC compatible
mode. Maximum 8 characters with a "." plus a 3 character
name extension).

[ShK]

DraCo seems to ask the floppy format when inserting a new floppy but there is also DraCoFloppy tool which allows to select already inserted floppies' format.

The padded roms can be found as attachments.

[Zarnal]

I tested OS3.9 Draco successfully.

Everything is going well with P96 (pic 1).

However there seems to be a problem with Cybergraphx (provided on the 3.9 Draco CD, pic 2, I need to recheck CGXMode and some variables). CGX 4.42.

The keyboard always doubles letters and numbers ( P96 or CGX ).

If I use DracoTools/DracoSystem and activate the Amiga keyboard, the keyboard becomes completely inactive.

[Toni Wilen]

Amiga keyboard is now supported (CIA-A required). This is another breaking chance: DraCo accelerator options has new option PC keyboard connected (default not connected!).

For correct PC keyboard only config, chipset keyboard connected should not be ticked.

[ShK]

No double letters with Amiga keyboard! With PC keyboard same issue as before...

[Toni Wilen]

PC keyboard double press/releases fixed.

[ShK]

Originally Posted by Toni Wilen

PC keyboard double press/releases fixed.

PC keyboard from 11.01.2024 20.21 build still gives a double letter for me... Amiga keyboard works as expected.

[Toni Wilen]

Better Retina/Altais ICS RAMDAC emulation, Draco+CGX modes now work. Mouse horizontal offset remains, no idea where it comes from.

EDIT: Mouse offset fixed (Happened only in DraCo+CGX config because CGX sets 64 pixel wide sprite)

[ShK]

Originally Posted by Toni Wilen

PC keyboard double press/releases fixed.

Seems I didn't have build with the fix last time, because now with 12.01.2024 also PC-keyboard works! No more double letters.

Confirmed also now mouse pointer fix to work with the newest build!

[Toni Wilen]

Floppy drive is now mostly emulated, including Amiga disk support.

PC formatted drives use normal PC FDC + PIO mode (FDC has 16 byte FIFO which makes this usable without DMA)

Amiga formatted reading is very low level, floppy RW head positioning/motor control/etc is done by PC FDC but reading is done by DraCo custom IO register that returns time between flux pulses.. All the decoding is done 100% in software. This also explains why it is not possible to write Amiga formatted disks.

[ShK]

Amiga DD floppies seems to work fine!