Myarc HFDC DSR and allocation error

[Swim]

Those are Tony's designations to differentiate them from existing versions.

 

If you stand still in the TI/Geneve world these days you get left behind.

[+9640News]

 

If you stand still in the TI/Geneve world these days you get left behind.

 

I stood still almost too long............

[+Schmitzi]

Hi,

 

as I have Barry Boone´s HFDC, here is the Eprom:

MyArc-HFDC-v11x-Schmitzi--Barry-Boone.bin

Thanks to Dexter for reading it out !

 

There is the "H11"-label on it, but maybe there is "something special" from Barry ?

 

xXx

[+InsaneMultitasker]

Hi,

 

as I have Barry Boone´s HFDC, here is the Eprom:

MyArc-HFDC-v11x-Schmitzi--Barry-Boone.bin

Thanks to Dexter for reading it out !

 

There is the "H11"-label on it, but maybe there is "something special" from Barry ?

 

xXx

can you compare this to the one included in MAME or a standard H11? See what is different?

[+Schmitzi]

Sorry I would if I could, but I don´t know how to.

And, if I would find some different bytes, I could not interpret anything....

[+mizapf]

 

$ unzip ~/mame/roms/ti99_hfdc.zip
Archive:  /home/michael/mame/roms/ti99_hfdc.zip
  inflating: hfdc_dsr.u34           
$ cmp hfdc_dsr.u34 MyArc-HFDC-v11x-Schmitzi--Barry-Boone.bin
$

 

No news is good news, especially in Unix contexts. This result means that the files are identical.

[+mizapf]

BTW, I'm taking this discussion on different DSRs as an opportunity to include ROM selection in MAME. Currently, this is (somewhat misleadingly) called "BIOS selection", but it means that you can select the ROMs for the main machine or for pluggable devices as they are available (and registered). I'm currently working on the Geneve emulation, splitting the GenMod off the common driver, and reorganizing it to support BIOS selection. This will make it easier once we have updated EPROMs for the Geneve and the HFDC.

 

You will then be able to select the BIOS like

 

 

mame64 geneve -bios rom098 -peb:slot8 hfdc,bios=h11

 

and also in the OSD. Putting the GenMod into a separate driver (inheriting from Geneve) has the advantage that BIOS selection will not mix Geneve ROMs with GenMod ROMs, and also to define the Memex being plugged in by default.

[+mizapf]

I wonder which version is used in MAME. The HFDC has been the default floppy controller from the start, and I don't remember any issues with file corruptions. So I should look out for a fragmented file, delete it, and write a new file?

 

While I was working on a reimplementation of the TI file formats in MAME, I discovered the said allocation issue. I tried to assemble SOMEFILE_S on a disk that was nearly full. The output file SOMEFILE_O already existed but was fragmented (sectors 347-359 and sector 25), and was supposed to be overwritten. Afterwards, TIImageTool reported an allocation error: Sector 26 was released, but it belonged to the FIB of another file.

 

I suspected an issue with my reimplementation, until I remembered this thread.

[+InsaneMultitasker]

Sadly, I haven't been able to further test the updated EPROM image I posted. While it seemed to fix the allocation error, it may have introduced a new error due to how I had to construct the fixed code. Unfortunately, many of our DSRs have seemingly simple routines that are branched into or used by other routines with little warning or indication, often to squeeze every possible byte out of the EPROM (of which the HFDC EPROM too few free).

[+mizapf]

I was actually wondering why back in those times, I used a separate floppy controller next to the HFDC controller; later I replaced the HFDC with the ASCSI, and I did not keep the HFDC, although it supported 80-track drives.

 

I feel some enlightenment coming from these findings . Maybe I did have those broken floppies and suspected a (hardware) issue with the HFDC. And I may have asked other people that gave me the same replies when I mentioned Myarc.