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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: nEx on February 16, 2005, 08:30:51 PM

Title: Escom A1200 Floppy fix
Post by: nEx on February 16, 2005, 08:30:51 PM

Hope this isn´t a old/boring question.

I have a A1200 (Escom model) and a small Circuit for the intern floppy fix.
So I don´t know on what Chip/Pin the Adapter-Part must be set.

Thanks for ya help!

Title: Re: Escom A1200 Floppy fix
Post by: bigdan on February 16, 2005, 10:06:15 PM

This one from Amtrade ?

www.amiga-hardware.com/showhardware.cgi?HARDID=389 (http://www.amiga-hardware.com/showhardware.cgi?HARDID=389)

I have still the doc if needed...

Title: Re: Escom A1200 Floppy fix
Post by: PG on February 16, 2005, 10:47:35 PM

Is documentation and maybe also circuit board layout available??
Im interested...:-)

Title: Re: Escom A1200 Floppy fix
Post by: nEx on February 17, 2005, 08:51:13 AM

Hm, the First Part of my Floppy fix would be set on the orginal Floppy Port Connector directly on the Motherboard. The Second Part looks like the "U7" Part on the Pictures...

@bigdan: Documentation were great! Think the Target-Chip and the Pin for the "U7" Part are the same.

Thanks for ya help!

Title: Re: Escom A1200 Floppy fix
Post by: bigdan on February 19, 2005, 06:57:40 AM

I've scanned the "real floppy fix" doc (german) and upload it on hardmiga.free.fr (http://hardmiga.free.fr/)

An english doc exist but not yet in my home, sorry ;-)

(http://www.amiga-hardware.com/display_photos/realfloppyfix_1_sm.jpg)

U7 and U8 are common names for CIA8520 on A1200, the arrowes must point on the right of the 1200 mainboard (in direction of panasonic floppy disk)...

Note the "Real Floppy fix" use the panasonic HD floppy (1.44 Mo) as DD (880 Ko), it only fix the "non-dos d7" panasonic problem.


Note : Amtrade HD (http://www.amiga-hardware.com/showhardware.cgi?HARDID=381) is the same thing for A4000 users... A1200 users could use it with a small wire between the interface plugged to HD floppydrive (TEAC, SONY or DELL) and a connector to clip on CIA to obtain the "missing" signal to use NON-DOS disks like demos, games..

Then the drive is a true HD floppy (1760 Ko) as the custom Chinon FB357A supplied with Amiga3000/4000.
---

  Réference         Name or function

     U0             68881
     U1             68020
     U2             Alice
     U3             Paula
     U4             Lisa
     U5             Gayle
     U6             ROM 512kx16 150ns
     U7             CIA
     U8             CIA
     U10-11         Optional flash memory 128kx8
     U12            Video Encoder
     U13            Keyboard chip
     U16-17         DRAM 256kx16 80ns
     U18-19         DRAM 256kx16 (optional)
     U20            Budgie
     U30            Vidéo DAC 8 bits

     X1             TTL Oscillator 28.63636 MHz NTSC
     X1             TTL Oscillator 28.37512 MHz PAL