External Disk Drive As Main Drive?

[catmando]

Nice job, pin outs for 14 pin din to 34 pin floppy connector are as follows


14pin din ----------------------- 34 pin connector

1 -------- 30
2 -------- 31
3 -------- 32
4 -------- 10
5 -------- 8
6 -------- 33
7 -------- 12
8 -------- 18
9 -------- 16
10 ------- 22
11 ------- 20
12 ------- 26
13 ------- 24
14 ------- 28

[Dal]

That looks odd to me - I was expecting all the odd lines at the 34 pin to be GND.

Here's the pinouts I was expecting going by the schematic for the motherboard and the 14pin pinouts:

Line------------14PinDin------------34Pin
RDATA-----------1--------------------30
S0SEL-------------2-------------------32
GND--------------3--------------------11 (Any Odd Line)
INDEX------------4--------------------8
DS1---------------5-------------------12
VCC--------------6--------------------NC
GND--------------7--------------------23 (Any Odd Line)
MOTOR----------8--------------------16
DIR---------------9--------------------18
STEP-------------10-------------------20
WDATA-----------11------------------22
WGATE-----------12------------------24
TR0---------------13------------------26
WP----------------14------------------28

Can you check those lines again?

Cheers mate.

[catmando]

Sorry forgot to reverse my diagram

1 -------- 30
2 -------- 32
3 -------- 31
4 -------- 8
5 -------- 10
6 -------- 12
7 -------- 33
8 -------- 16
9 -------- 18
10 ------- 20
11 ------- 22
12 ------- 24
13 ------- 26
14 ------- 28

[Dal]

Right that makes more sense- wasn't sure about the ds0/ds1 lines. Cheers mate!

[1024MAK]

Hm, well if you still are unsure check http://www.atari-forum.com/viewtopic.ph ... 48#p166496
The details here are confirmed to work.
Note that on some drives pin 1 is not always ground.

[Dal]

Yes of course pin 1 is HD select. Better keep that off the GND line

[DrCoolZic]

Line------------14PinDin------------34Pin
RDATA-----------1--------------------30
S0SEL-------------2-------------------32
GND--------------3--------------------11 (Any Odd Line)
INDEX------------4--------------------8
DS1---------------5-------------------12
VCC--------------6--------------------NC
GND--------------7--------------------23 (Any Odd Line)
MOTOR----------8--------------------16
DIR---------------9--------------------18
STEP-------------10-------------------20
WDATA-----------11------------------22
WGATE-----------12------------------24
TR0---------------13------------------26
WP----------------14------------------28

I believe pin 5 & 6 are incorrect - 5 is DS0 and 6 is DS1
see http://info-coach.fr/atari/hardware/int ... _Connector

[wongck]

I believe pin 5 & 6 are incorrect - 5 is DS0 and 6 is DS1
see http://info-coach.fr/atari/hardware/int ... _Connector

IIRC, the PC floppy are all hardwired to DS1 and to make it work as device# 0, you need to swap them.

[DrCoolZic]

I believe I have a broken external Atari FD unit somewhere
I'll try to find it in the attic to see how the DIN is connected to the flat cable

[Dal]

I believe I have a broken external Atari FD unit somewhere
I'll try to find it in the attic to see how the DIN is connected to the flat cable

Check out Catmando's post above - he has done this for me already and essentially it is the same as my pinouts apart from the switched DS0/DS1 lines. Just waiting for my FDD cable to arrive from 16/32 so I can hack it for the job

[1024MAK]

Hm, well if you still are unsure check http://www.atari-forum.com/viewtopic.ph ... 48#p166496
The details here are confirmed to work.
Note that on some drives pin 1 is not always ground.

The details I refer to are for a drive that responds with the drive select "DS" jumpers set up correctly. This does depend on which model of Atari you have and how the option jumpers (links) in the Atari are set. For most machines that have an internal drive, on the main PCB (motherboard) DS0 and DS1 for the external DIN drive connector are both electrically linked to the DS1 signal.
That is to say if you have a floppy drive that is set to respond to either DS0 or DS1 (and the Motor On "MO" signal is wired as per the normal floppy standard and not the IBM PC arrangement) the drive should work as a second drive (drive B) without any problems (well apart from maybe the disk change sensing - but that's another story).
For Atari's that do not have an internal FDD, you should work out which drive select signal the drive responds to/and/or change the DS jumpers / links (where possible) or swap the DS0 and DS1 lines (and if needed do the same with the Motor On "MO" signal).
Indeed if there is no internal drive, once you have the drive select signals sorted you can have two external drives working well.
Of course it was just so much easier and less painful when floppy drives had proper jumper pins (jumper shunts)
You may also like to know that I have checked two "proper" external drives (but both from the same manufacturer but they were not supplied by Atari) and the connections are the same with the following exceptions: they used pin 1 and pin 33 only for each of the 0V ground connection to pins 3 and 7. Both these drives have 14 pin DIN mail (plug) connectors with the cable going inside the drive and no provision for another FDD (no through 14 pin connector).

[Dal]

This will be for a HxC floppy emulator that I wish to use between my ST's and Falcon. I have bought a case for it and I plan to wire up the 34-way to a 15-way D-SUB mounted to the case (the 2 row variety rather than the VGA type). I guess seeing as I can assign DS0 or DS1 in software for the HxC, it would make more sense not to cross over the DS0/DS1 lines in the case and keep it all simple.

With the complete setup I will be able to use the HxC on the ST as drive A or B and on the Falcon as Drive B (I have no requirement to boot from the HxC on the Falcon for now).

[wongck]

This will be for a HxC floppy emulator that I wish to use between my ST's and Falcon. I have bought a case for it and I plan to wire up the 34-way to a 15-way D-SUB mounted to the case (the 2 row variety rather than the VGA type). I guess seeing as I can assign DS0 or DS1 in software for the HxC, it would make more sense not to cross over the DS0/DS1 lines in the case and keep it all simple.

With the complete setup I will be able to use the HxC on the ST as drive A or B and on the Falcon as Drive B (I have no requirement to boot from the HxC on the Falcon for now).

Yes, don't cross it. Keeping it separated means you can switch between D0 & D1 at will,.

[Dal]

Thanks everyone - finished all the soldering this evening and everything worked first time. I have wired up the ports and the cable for the HxC and hooked it all up. The DS0/DS1 switch toggles between the internal drive and the HxC connected to the EXT FDD port as expected.

Tomorrow I will sort the casing out for the HxC and post up some pics of it all finished.

Cheers!!

[Dal]

Took me a while to get around to sorting the casing out. Here's the finished article:

IMG_0148.jpg

IMG_0150.jpg

IMG_0151.jpg

IMG_0154.jpg

IMG_0156.jpg

IMG_0158.jpg

IMG_0160.jpg

[wongck]

You made that case? WOW you're good at metal work.

[Dal]

Alas - no, the case itself was a project box from Maplin that, for a change, was exactly the size I was looking for (I'm still yet to find a suitable case for my NetUSBee ).

[Dal]

I have now added a Wiki article that goes through the entire process complete with the parts list and pinouts I used for cable etc.

Check it out at:

http://www.atari-forum.com/wiki/index.p ... C_To_An_ST

Link also added to the Hardware Mods index page

[catmando]

I have now added a Wiki article that goes through the entire process complete with the parts list and pinouts I used for cable etc.

Check it out at:

http://www.atari-forum.com/wiki/index.p ... C_To_An_ST

Link also added to the Hardware Mods index page

V. Good Wiki, but I think it should be two wiki's with one referencing/linking to the other. Can you add a photo of how the USB coupler is connected as I think that will help people out a little too.

[wongck]

[wongck]

I have now added a Wiki article that goes through the entire process complete with the parts list and pinouts I used for cable etc.

Check it out at:

http://www.atari-forum.com/wiki/index.p ... C_To_An_ST

Link also added to the Hardware Mods index page

Oops.... can you add it again to the AF Wiki, if you have a old copy of it ?
It's was not in the restore.
Thanks.

[Dal]

Will do! Thanks for the nudge.

[Spider2012]

I've purchased the HxC SD Card reader and I'm looking at trying to get it to work with the internal floppy drive on my STE, I thought about putting the card reader permantely inside the case above the external floppy connection at the back - on the STFM there is plenty of room (the STE has it's memory in this area but I believe is only a small obstacle). The plan is to cut a slot in the rear of the case for the SD card and create a seperate pcb with 3 buttons soldered to wires connected to the original buttons on the HxC Card Reader and mount them in the lid lid of the STE - still working on the display aspect as I haven't found a suitable connecting cable yet.

I have found a company in the US who can make the ribbon cable extension (that was more difficult to find than you think) that plugs straight into the Atari Ribbon cable (basically a 24" extension with an exta 34 pin connection point), around $10, and a 'Y' splitter to power both the SD card reader and the floppy drive at the same time (will the Atari STE damage itself by drawing double the power through the same point?).

Given what I've read there would seem to be an issue in the way the Atari ST/E addresses multiple FDD on the same chain? would my idea work if the Card Reader is set to 'B' drive and the floppy remians the 'A' drive? what are the chances of reversing this? I'm still waiting on some final bits of kit to arrive to put my idea to the test.

[troed]

would my idea work if the Card Reader is set to 'B' drive and the floppy remians the 'A' drive? what are the chances of reversing this? I'm still waiting on some final bits of kit to arrive to put my idea to the test.

Did you get any further on this? I'm contemplating various ways of connecting my HxC atm - since I have more than one ST a solution using the external floppy connector is of interest. As I've understood it, that would need a ds0/ds1 switch as described earlier to get full compatibility when booting things.

[braincell1973]

does anyone have the 15pin to amiga external from the above project as i would like to se a SD HXC floppy emulator for multiple systems ?