THESE PCBs ARE NOT TESTED YET
This is a set of adapter PCBs and printable snap covers to build a nice version of FluxEngine
I am not the creator of FluxEngine itself, just this adapter PCB and printable cover.
Most people probably do not need any of these pcbs. They are really just to provide convenient support for 8-inch drives.
If you're not trying to use 8-inch drives, then you don't need any adapter pcb like this.
The FluxEngine pinout is already designed so that you can just solder a 34-pin connector directly to the CY8CKIT-059 fpga board.
You can use the BOM link below and delete everything but the CY8CKIT-059 and the 34-pin connector, no pcb, no printed cover.
The PCBs are designed to NOT need to be soldered. You can connect and remove and reconnect the fpga board without, and without needing to install actual sockets. You CAN still solder them normally if you want to make a permanent FluxEngine, you just don't have to.
It means you can swap the same fpga board between all 3 (so far) hat versions, and then still also use the fpga board on a breadboard when not using it for FluxEngine.
What you do is solder pins to the bottom of the fpga board the same as if you were using it on a breadboard. And that's it. You can install actual matching sockets on the hat PCBs, but you don't have to. The zig/zag pin row layout on the hat PCBs makes solid electrical contact with the pins without needing a socket.
For the sake of the solderless pin connections, I suggest getting the PCBs made with ENIG finish (gold plating on the copper).
It's not required though. Honestly the way the square edges of the pins bite into the via walls it probably will never make any difference.
Some fabricators charge more than others for ENIG. OSHPark is always ENIG no matter what, so that's easy. But between PCBWAY, JLCPCB, and Elecrow, Elecrow charges a lot less for ENIG.
The cover (both styles) prints easily with any basic home FDM printer with PLA. I actually use a $150 Monoprice from 6 years ago.
But also these days most of the PCB shops also offer 3d printing, so you can get the pcb and the cover printed professionally in sintered nylon from the same place on the same order.
The link below is to PCBWAY only because it's the most convenient where you can just click "buy" on something already pre-loaded, but actually if you go to Elecrow and just upload the gerber zip and cover stl, it's just as simple and significantly cheaper, especially with ENIG.
BOM from DigiKey
PCB and Cover from PCBWAY
If you don't already have a convenient way to power the floppy drive(s) externally:
Molex power supply
Molex to Berg splitter
Molex to Molex splitter
Floppy drive cable
There are several versions of printable cover in releases, all generated from the same OpenSCAD source.
Two main styles, simple and fancy, in three sizes each, lowprofile, default, and one for if you have full pin sockets installed.
The jumpers only affect the 50-pin connector for 8-inch drives.
Connects either /DSKCHG or /READY output from the drive to the /DSKCHG input on the host.
Install jumper on DC by default.
Connects the /MOTB (motor-B-on) output from the host to either the /DOOR-LOCK aka /IN-USE, or /HEAD-LOAD input on the drive, or neither, or both.
Usually not needed, but if needed, you may need one or the other or both.
Don't short either position by default, but do stow two inactive jumpers.
Some CDC drives like the 9404 and 9406-4 lines are Shugart compatible, and so for those just use the SA850 hat like any other Shugart bus drive.
But many CDC drives had totally different pinouts and interfaces, not remotely Shugart compatible.
There were several different interfaces and configurations, but of those, it does appear that most drives probably fall into one of two possible pinouts.
The two tables below come from two CDC manuals covering many similar drive models spanning several years.
Left: CDC FDD FSM ('79)
Right: CDC 9406 FSM ('82)
There are special hats for the most common CDC pinouts.
The "CDC-daisychain" hat supports all the green highlighted models.
The "CDC-standard" hat supports the blue and purple highlighted models.
"standard" is mis-named because what CDC called "standard interface" in the manuals was several different pinouts and interfaces.
But of the many "standard" pinouts, 2 are the same except for STEP+DIRECTION vs STEP_IN/STEP_OUT, and most models that aren't daisychain seem to be one of these two versions of "standard".
So the CDC-standard hat includes logic to convert the STEP+DIRECTION signals from the FluxEngine to STEP_IN/STEP_OUT signals for the drive, and jumpers to select whether you want STEP+DIRECTION or STEP_IN/STEP_OUT.
For drives that need STEP_IN/STEP_OUT, install the 2 jumpers on the side marked OLD.
For drives that need STEP+DIRECTION, install the 2 jumpers on the side marked NEW.
If you don't need the OLD option, you don't need to populate C1 or U1 or the jumper pin header. Just use solder in place of the NEW jumpers and leave the U1 and C1 footprints empty.
NONE OF THESE ARE TESTED YET
THIS IS ALL JUST THEORY AS OF NOW
I have a 77618019 drive which will be a test of the CDC-daisychain hat, but not done yet.
CDC hat BOMs
CDC-daisychain:
Same as the default Shugart-compatible BOM, but delete the pins and jumpers.
CDC-standard:
Default BOM, delete the pins (keep the jumpers), add the following:
screw terminal header
screw terminal plug
74HC00 tssop
C 0.1u 0805
2x3x2.54mm pin header
The AC & DC power connectors were the same on many drives.
These are the cable-side connector housings and female pins needed to make proper cables to connect to most drives.
3-pin AC power:
Housing: AMP/TE 1-480700-0
Female pins: AMP/TE 350536-1
6-pin DC power:
Housing: AMP/TE 1-480270-0
Female pins: AMP/TE 61117-1
They do make dual-output power supplies that output both 5v and 24v, but it's actually cheaper to buy seperate supplies.
A typical drive draws about 1.0A-1.5A from either DC rail while working.
Here are a couple of supplies just for convenience & reference:
5V 3A Meanwell
24V 3.2A Meanwell
The CDC manuals do not say this anywhere, but many drives have a variant of the 50-pin connector with two polarity keys instead of one in the center. The drawings and actual part numbers in the service manuals only show the normal single-notch type.
A normal plug with polarity key does not fit. Non-polarized plugs fit, but here are a couple of fully polarity-keyed female IDC plugs that fit:
Omron XG4M-5031-T
Hirose HIF3BA-50D-2.54R
Connector housing & contacts to fit the 7-pin power connection on CDC drives.
The pins are .156" pitch which is not uncommon, but a .031"x.062" flat blade shape not square, so the "AMPMODU MOD I" is important here, as is specifically the high-pressure version of the pin receptacle.
Only 4 pins are connected, so you could uses as little as a 5-position housing, but ideally you still want a housing with 7 or more positions and receptacles installed for all 6 pins, because the extra 2 n/c pins provide extra retension friction and strain relief.
TE 87159-7 - AMPMODU MOD I receptacle housing, 7-pin non-locking keyed (cut the key bumps off)
TE 102100-2 - AMPMODU MOD I pin receptacle, non-locking high-pressure 18-22awg gold-30uin (need 6)
TE 87116-2 - AMPMODU MOD I keying plug (need 1)