Update README.md

README.md

@@ -12,19 +12,19 @@
 ![](PCB/out/FluxEngine_Hat.bottom.jpg)
 ![](PCB/out/FluxEngine_Hat.svg)
 
-These PCBs ARE NOT TESTED YET.
+THESE PCBs ARE NOT TESTED YET
 
-This is an adapter PCB and printable snap cover to build a nice version of [FluxEngine](http://cowlark.com/fluxengine/)
+This is a set of adapter PCBs and printable snap covers to build a nice version of [FluxEngine](http://cowlark.com/fluxengine/)
 
-I am not the creator of FluxEngine itself, just this connector PCB and printable cover.
+I am not the creator of FluxEngine itself, just this adapter PCB and printable cover.
 
-Most people probably do not need this pcb. It's really just to provide convenient support for 8-inch drives.
+Most people probably do not need any of these pcbs. They are really just to provide convenient support for 8-inch drives.
 
-If you don't need to support 8-inch drives, then you don't need any adapter pcb like this.  
+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 could just use the BOM link below and delete everything but the CY8CKIT-059 and the 34-pin connector, no pcb, no printed cover.
+You can use the BOM link below and delete everything but the CY8CKIT-059 and the 34-pin connector, no pcb, no printed cover.
 
-## PARTS
+## Parts
 [BOM from DigiKey](https://www.digikey.com/short/q5zh79n9)  
 [PCB and Cover from PCBWAY](https://www.pcbway.com/project/shareproject/FluxEngine_Hat_e3000eb5.html)
 
@@ -34,7 +34,7 @@ If you don't already have a convenient way to power the floppy drive(s) external
 [Molex to Molex splitter](https://amazon.com/dp/B00007JO36)  
 [Floppy drive cable](https://amazon.com/dp/B07KDJTMGP)  
 
-## Enclosure
+## Cover
 
 There are several versions of printable cover in the CASE directory.
 
@@ -53,11 +53,11 @@ There are several versions of printable cover in the CASE directory.
 
 The cover prints easily with any common FDM printer with PLA.
 
-The PCBWAY link above can provide both the PCB and the cover. The buy link to the right is for the pcb. To get the cover scroll down the page to the FluxEngine_Case.stl file and it has it's own buy link.
+The PCBWAY link above can provide both the PCB and the cover. The buy link to the right is for the pcb. To get the cover scroll down the page to the STL file and it has it's own buy link.
 
 You can also get both the pcb and the cover at the same time on the same order from Elecrow for about $13 including shipping.  
 Get the gerber.zip and STL from [releases](../../releases).
-Choose high strength nylon for the 3d printing to get a strong black part.
+Choose high strength nylon for the 3d printing to get a strong black part. It doesn't really need the strength of nylon, but resin will probably be too fragile.
 
 ## Configuration
 
@@ -75,17 +75,34 @@ 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.
 
-# Control Data / Magnetic Peripherals 8-inch drives
+# Control Data Corporation / Magnetic Peripherals Inc / Honeywell 8-inch drives
 
-CDC/MPI drives seem to have been pretty common, but have a totally different pinout than Shugart. They actually have several different pinouts and some are completely custom and incompatible, but one of the pinouts, with only a pin or 2 two different but no pins we care about, seems to be used by most models. So I'll call that pinout "CDC standard".
+CDC drives seem to have been pretty common. The same drives appear under a few different names because of the way they were [OEMed by MPI to CDC and Honeywell](https://en.wikipedia.org/wiki/Control_Data_Corporation#Magnetic_Peripherals_Inc.), and then CDC also sold them to yet others like [Centurion](https://www.youtube.com/watch?v=GmuDJC1gJOo).
 
-The two tables below come from two CDC manuals covering many similar drive models.  
+CDC drives have a totally different pinout than Shugart. They actually have several different configurations and some are completely custom and incompatible, but most models seem to have used slight variations on one pinout. So I'll call that pinout "CDC standard".
+
+----
+
+EDIT: I got this backwards. Both manuals say:
+```
+3.4.2  DC POWER CONNECTION  
+DC power (user-supplied) for standard FDD models is transmitted from the controller  
+via the I/O cable through the interface connector (J1) on the printed-circuit board.  
+Daisy-chain FDD models receive DC power (user-supplied) through a power cable which  
+interfaces with its mating connector (J4) on the printed-circuit board.
+```
+So the pinout I called ALT1 should be called "Standard"  
+and the pinout I called STD should be called "DaisyChain"
+
+----
+
+The two tables below come from two CDC manuals covering many similar drive models spanning a few years.  
 Left: [CDC FDD FSM ('79)](PCB/datasheets/CDC_77834769_Y__FDD_FSM.pdf)  
 Right: [CDC 9406 FSM ('82)](PCB/datasheets/CDC_77614903_AM__9406_FSM.pdf)  
 
 ![](PCB/datasheets/CDC_FDD_pinouts.png)
 
-There is a hat version for "CDC STD" which matches all the green highlighted drives, and (I'm guessing) probably covers most CDC/MPI drives.
+There is a special hat for CDC which should work for all the green highlighted drives, and (I'm guessing) probably covers most CDC/MPI/Honeywell drives.
 
 There is also a hat version for "CDC ALT1", the purple highlight, simply because at least that pinout has the necessary signals that it's possible.  
 I have no idea if those models are common, or if the power really needs to be on the data cable or if the drives still have a simple way to provide the DC power directly. The hat includes the power connections simply because it was possible without even increasing the size of the pcb. The drive draws less than 1.5A on either rail, and both the screw terminals and the traces are good for over 5A. So although I don't really *recommend* powering a drive that way if there is any other option, it should be fully safe to do so.