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Epson QX owners - please join

Hi, i have some news about "misteriouse" Epson QX-11, QC-10, Q6101 aka Abacus Project :)

I need write more post in this thread, until i are able to gain enough points to create a separate thread.

Until now, This strange and forgotten model of Epson Computer, join three persons about the globe...
 

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Hello everybody... User ettore, gigabajcior and myself have been working together in restoring and reverse engineering the three QX-11 machines we have.
The QX-11 Setup utility have the option to set the drive letters used by each disk drive the QX-11 can use. As you can see from the picture, the QX-11 could use up to 12 drives or better said 12 storage units.
qx11_setup_screen.jpeg

Units A and B are assigned to the two internal floppy drives that come installed in the QX-11 (The QX-11's base configuration was a 128k RAM 1 31/2" floppy drive, but I never saw a machine other than the one with two physical 3.5" floppies). Drive letter G is assigned to the option 10G hard drive. Drive I is reserved for a RAM disk you could create using the very same setup utility. The QX-11 could also use 2 ROM expansions. 1 of those ROM expansions could be added as a ROM cartridge you could insert in a cartridge slot on the machine's front panel. The second ROM extension was added through an add-on card connected to an internal expansion slot.

Drives C,D,E and F are the most interesting ones. This 4 drive letters are assigned to external floppy drives.
There is no need to open the machine to add an additional controller card nor the need to add a driver. The QX-11 will take an EPSON external floppy drive enclosure (possible options would be a TF-15, a TF-20 or a PF-10).
This external floppy drives communicate through the machine's serial port using the EPSP (EPson Serial Protocol) for external drives. We are reverse engineering the EPSP commands the QX-11 uses to talk with the drive, but this option give the QX-11 to use an external device (an sd-card reader device for instance) without any modification to the hardware, just through the serial port. No need to adapt a gotek, or to open the case and figure out the connector.

The QX-10 also supported the EPSP protocol over the serial port, as you could use the TF-10 external floppy drive enclosure on it.

I also have a QX-16 and I wonder if a QX-16 would support a EPSP floppy over the serial port. Once I have my QX-16 working I will test for possibilities.

If any of you guys who have a QX-16 knows of have ever try to connect an external floppy to the QX-16 through the serial port, please let me know.
 
Hi Fred, Regards!

Out of box, the emulated EPSP projects that we found on internet created for PX-4, PX-8 and HX-20 computers didn't work with QX-11 computer. We found some differences in the handshaking, and functions called from QX11 with the CP/M flow. I believe those differences and functions are related to MSDOS and FAT filesystem. Maybe real storage units as TF-20, PF-10 had them implemented in their roms. :unsure:

As soon, i will able to create a new thread, i will post the details of this.
 
fjkraan said:
It seems the QX-11 is a kind of merge of the QX-10 with the PX-8/PX-4 and PX-16 lines of computers. It even has the ROM cartridges. The External Disks using EPSP can be emulated with cheap hardware: https://electrickery.nl/comp/tf20/pxdisk/

Greetings,
Fred Jan
Click to expand...
Hey Fred

So the QX-11 was not a merge between the qx10 or any of the epson cp/m portable computers. The QX-11 was actually one of EPSON'S first msdos computers.

The QX11 included msdos 2.11 in ROM (64KB of ROM for the QX11 and 128K of rom for the QC11 [the Japanese version of the qx11]). On the QX11's design, EPSON reduced the overall size of the motherboard by integrating the majority of its hardware into 5 gatearray chips. As a consequence the QX11 does not have a 7220 video chip like the QX10 but an EPSON produced video processor (GAVDP) with 48k of VRAM. Same thing for memory management (GAVRMR), Interrupts and dma control (GAVINT ) , IO (GAVNIO) and Floppy Controller (GAFDDC).

The QX11 also had two joystick ports, a 3 voices sound chip (same sound chip used on the tandy 1000, nintendo nes and the ibm pc jr) and and external cartridge slot (never got to see one). As part of our reverse engineering is that we found out the QX11 will support a fd15, fd20 and or a pf10 EPSP external floppy drives, although I'm not sure if the units sold for the qx11 had a different firmware that the ones sold as an option for the hx20. I found out there is also a FD20 for the NEC PC in Japan, probably with a different firmware too.

It is worthed to mention that the Qx11 also had an optional IBM compatible video card (needed to run certain msdos applications) and and additional external hard drive.

The machine that happens to be a merge made out of two different machines is in fact the Epson QX16. The QX16 was never released in Japan. The QX16 was released in America (never released in Japan) and was in fact a QX10 chassis (same power supply and same z80 design) but EPSON also used part of the design from the qx11; for instance, the QX16 had the GAFDDC. The GAFDDC (the glue between the upc765 disk controller and the EPSON's made floppy drives.) the gafddc gatearray was also used latee on the equity I series machines.

The QX16 also used the optional IBM video card created for the QX11, same gatearrays and same crt controller but on the qx16 this cga card came installed as standard equipment and not as an option (in the Qx11 you have to load a driver to switch the video output from the native video to the cga card, my understanding is that you don't need a driver to switch from the 7220 video to the ibm video mode when booting msdos in a qx16)

The qx16 came with the same msdos 2.11 that was included on the qx11 but in the qx16 you need to boot from disk instead of rom. The Qx-16 actually used the same keyboard from the qx11 and the same crt monitor. The qx11 was a smaller machine with a smaller power supply than the qx10, that's the reason why the qx11's monitor has its own power supply. Even though the qx16 uses the slveey same power supply as the qx10, the qx16 was not wired to power the monitor from its internal power supply.

Sorry for the long post but if you actually want to get more information about the qx11 you can also visit out git repository with pictures and additional details, including the qx11 roms.

qx11 github

I am actually working on a qx11 driver for mame. I'm still not emulating all the hardware because there is not much information about the QX11 Gatearrays, but at least I have video and keyboard working and I'm close to get the floppy drives working (hence the discovery of the qx11 support for epsp)

hope this long post was helpful!
 
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Thanks for the clarification, I could have known, it is all in the thread.

The PX4/8 use EPSP at the sector level, which are 256 bytes. The QX11, as a DOS machine would probably use 512 byte sectors. The HX-20 uses EPSP at the file level, with different commands. The TF-15 and PF-10 only supports the PX-4/8 set of commands, the TF-20 also does HX-20 commands.
The EPSP commands of the TF-15 and PF-10 are fixed by the firmware in ROM, the TF-20 commands are part of the floppy based OS. I never tried to fully disassemble the ROMs or floppy code.

At one time I created a duplex serial monitor to check the EPSP from and to the PFBDK floppy emulator: https://github.com/electrickery/DualSerialMonitor.

Greetings & success,

Fred Jan
 
Hi
fjkraan said:
Thanks for the clarification, I could have known, it is all in the thread.

The PX4/8 use EPSP at the sector level, which are 256 bytes. The QX11, as a DOS machine would probably use 512 byte sectors. The HX-20 uses EPSP at the file level, with different commands. The TF-15 and PF-10 only supports the PX-4/8 set of commands, the TF-20 also does HX-20 commands.
The EPSP commands of the TF-15 and PF-10 are fixed by the firmware in ROM, the TF-20 commands are part of the floppy based OS. I never tried to fully disassemble the ROMs or floppy code.

At one time I created a duplex serial monitor to check the EPSP from and to the PFBDK floppy emulator: https://github.com/electrickery/DualSerialMonitor.

Greetings & success,

Fred Jan
Click to expand...
Hi Fred,

Thanks for you quick response,

Unfortunately, none of us have access to those floppy based storage devices, I have the 10Mb Hardisk, but is another kind of animal :).

Talking with Victor (Vprada) I suggested the idea of simulating the communication between the QX11 and a real floppy storage device. He is doing a great work on Mame emulator since he managed to boot the emulator with the original QX11 Bios,

Although I understand there's still a long way to go. Just as we have access to the real QX11, we can simulate the conversation step by step with the tool you're suggesting, or a program like the Vfloppy that acts as an initiator and simulate the QX11 in the handshaking.

Sure, well for now the other way is the trial and error, or as we say here, "shooting arrows ---> -----> 😂😂".

Regards
 
Grettings.

I've been working on developing a MAME driver for the QX-11. I can finally share that I reached the point where i have a working prototype. At this point I have some video, sound, and I'm able to read floppies. For the QX11 Epson developed 5 custom gatearrays, so emulating that hardware have been really difficult, but with a lot of testing and debugging I've been able to "fake" the behavior of some of this chips in order to have a quasi functional machine.

If you want to take a look please visit the git repository for the QX11 in my git page. Special thanks to user ettore, who was able to extract and share the ROM images from his QX-11 and also shared all the original software he have on his QX-11.

QX11 MAME driver
 
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