A/B drive swap switch

Update your old 720k to a 1.44 drive etc.
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A/B drive swap switch

Post by Gunstick » Sat Feb 10, 2018 6:33 pm


There is an advantage to have drive A external to the ST as it allows to have a single Gotek/HxC to use on multiple STs.
Here are some infos about how to put a switch in the ST which changes the internal to external drive and vice/versa

But it needs cutting YM pins or PCB traces. And today people try to avoid modding too much the old STs. So is there another solution?

Look at this page
http://info-coach.fr/atari/hardware/int ... _Connector
which says that you can put dirve0 signal onto the external connector instead of the drive1 signal. This is done on the W2 (STF) or W300/W301 (STE) soldering pads.

This means that selecting A will now switch to both external and internal drives, which obviously is bad.
But as the internal drive is on a ribbon cable, it should be not too difficult to make the internal get the drive1 signal.

One could put a header in there and have a switch somewhere.

w2.png (319.97 KiB) Viewed 114 times

w30w301.png (189.67 KiB) Viewed 114 times

Or dump the internal drive altogether and run A and B as external.

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Re: A/B drive swap switch

Post by exxos » Sun Feb 11, 2018 1:00 am

You could try talking to petari nicely as he is doing a lot of mods to TOS lately, to see if a software patch could be done to swap AB.
4MB STFM 1.44 FD- VELOCE+ 020 STE - 4MB STE 32MHz - STFM 16MHz - STM - MEGA ST - Falcon 030 CT60 - Atari 2600 - Atari 7800 - Gigafile - SD Floppy Emulator - PeST - HxC - CosmosEx - Ultrasatan - various clutter

https://www.exxoshost.co.uk/atari/ All my hardware guides - mods - games - STOS
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Re: A/B drive swap switch

Post by Gunstick » Thu Feb 15, 2018 12:34 am

I guess an AUTO program can swap both drives when TOS/GEM is running. But for demo/games it's useless to change TOS, many switch off TOS and hammer around on the WD/YM directly.

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