Formatting

HxC Floppy emulator support for all others computers...
Jeff
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Re: Formatting

Post by Jeff » Fri Dec 20, 2019 12:34 am

I think that you can probably find the opcodes sequence but with different jump addresses :

Code: Select all


ED42            SBC     HL,BC         .B
DAXXXX          JP      C,XXXXH       .}l	; Motor Fast test
017D00          LD      BC,007DH      .}.
B7              OR      A             .
ED42            SBC     HL,BC         .B
D2XXXX          JP      NC,XXXXH      ..l	; Motor Slow test
3E88            LD      A,88H         >.
32XXXX          LD      (XXXXH),A     2.F

bazzano
Posts: 10
Joined: Thu Dec 12, 2019 10:18 pm

Re: Formatting

Post by bazzano » Fri Dec 20, 2019 3:11 am

After alot of investigation I successfully patched FORMAT/CMD command to remove "motor too slow" error, and now formatting works.
Timing speed is software based by comparing a few values, so simply removing the conditional jump made the job.

This is the code I found:

Code: Select all

5546 2113f4    ld      hl,0f413h
5549 19        add     hl,de
554a 21685a    ld      hl,5a68h		--> motor too fast
554d d2b256    jp      nc,56b2h
5550 2197f3    ld      hl,0f397h
5553 19        add     hl,de
5554 218e5a    ld      hl,5a8eh		--> motor too slow
5557 dab256    jp      c,56b2h		--> CHANGE THIS TO NOP-NOP-NOP TO PATCH <--
555a c9        ret     
This fix is related to NEZ80 with NE-DOS version G.1.0. I don't know if it's similar to NEWDOS 2.1, but maybe. I'll need to check it.

Now I need to fix the COPY command that has the same problem when copying an entire floppy: infact it makes a formatting at the start, and it returns the same error.

Thank you.
Roberto

Audronic
Posts: 63
Joined: Thu May 22, 2014 3:28 am
Location: Williamstown Victoria Australia

Re: Formatting

Post by Audronic » Fri Dec 20, 2019 5:49 am

Hi Bazzano

Well done nearly there.
Can you copy individual files ?

Keep going almost there.

There is a good site Italian I think may be interested in you Patch(s)

Ray
If it ain't Broke then PLEASE DONT fix it.

Procrastinators Unite !

Jeff
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Re: Formatting

Post by Jeff » Fri Dec 20, 2019 9:22 am

Well done ! :)

bazzano
Posts: 10
Joined: Thu Dec 12, 2019 10:18 pm

Re: Formatting

Post by bazzano » Fri Dec 20, 2019 1:37 pm

Audronic wrote:
Fri Dec 20, 2019 5:49 am
Hi Bazzano

Well done nearly there.
Can you copy individual files ?

Keep going almost there.

There is a good site Italian I think may be interested in you Patch(s)

Ray
What site? http://www.z80ne.com ?
It's mine... :-)

Roberto

Audronic
Posts: 63
Joined: Thu May 22, 2014 3:28 am
Location: Williamstown Victoria Australia

Re: Formatting

Post by Audronic » Fri Dec 20, 2019 11:12 pm

Hi Roberto

Yes thats the site.
Then you should be congratulated for such a comprehensive site.

Please keep up the good work.

I have worked with TRS-80s for to long over here in Australia.

Seasons Greetings. Ray
If it ain't Broke then PLEASE DONT fix it.

Procrastinators Unite !

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