CDC 5 1/4 floppy 77711501 / 77711800 specs, update - test-drb@ccmp.vtda.org

9 Dec 2007

-------------- Original message from "Chuck Guzis" <cclist at sydex.com>:
-------------- 

...
  Well, I can tell you that MPI made 100 tpi FH
drives--I have two of 
 them on my shelf here, date codes are 81-82. Unfortunately, the 
 labels have dried up and dropped off, so I no longer have any idea of 
 what their part number is. I've also got a couple in another 
 machine, but it's a bear to get at them. 

 Does the drive have a little "daughterboard" plugged into the main 
 PCB with a 74ls123 on it? That'd be the "Drive Ready' circuit. I 
 don't know if all MPI 100 tpi drives had this though. 

 "Micropolis" type 100tpi drives also have a slightly different pinout 
 than normal "Shugart" type drives (this includes the Tandon TM-100- 
 4M). A big difference is that READY is pin 6, not 34. Maybe that's 
 what's causing your drive error. 

 Just guessing... 

 Cheers, 
 Chuck 

Hi, 

Well Chuck  and Paxton where right there.  I  took a chance and pulled a 
Quad denisity drive out of  a Motorola system I got from Paxon (sorry Tony.
I see your post)  and all is well.  It took 16 disks to back up  close to 10 megs. 
I had to bulk erase the disks (DSDD) for them to work with either drive.  

Anadisk finds 80 cylinders and is able to read the whole floppy with out errors
( using a 1.2HD drive.)

 I have not workd with Image disk yet.

I'm still out in the dark on the OS and how to make a bootable floppy. I cant
get past there Menu system   It seems to run on or with some type of basic.

Below is a Boot screen for those with interest. The System is a small desk top
6 serial port business system.

Thanks, Jerry
 ......................................................

                              <I-TIMERS><I-USARTS><I-PIC'S
><I-DMA'S >
BOOTSTRAP LOADER VER 120A 31MAR83  S/N:000794
                              <I-TIMERS><I-USARTS><I-PIC'S
><I-DMA'S >
                              <I-FLOPPY><I-MEM&CH><MEM DATA><MEM
BANK>
                              <MEM ADDR><HD SETUP><HD READI><VFY
INCP>
                              <HD READL><VFY LOAD>
STARDOS SYSTEM UTILITIES  REV 242B  10JAN84

STARDOS BASIC LOADER
1) ENTER MASTER MENU
2) ENTER SYSTEM UTILITIES MENU
ENTER YOUR CHOICE 2

                  ###########################################
                  # STARDOS SYSTEM UTILITIES - VERSION 242B #
                  ###########################################

 1) ENTER MASTER MENU
 2) INITIALIZE DEVICE
 3) COPY DISKETTE
 4) COPY STARDOS
 5) RECONFIGURE
 6) BINARY BACKUP HARD DISK
 7) BINARY RESTORE HARD DISK
 8) INITIALIZE FILE SAVE DISKETTE
 9) HARDWARE CONFIGURATION
ENTER YOUR CHOICE 1

                           *** S T A R D O S   II ***
                       BASIC RELEASE 10.7  REV C 05JUN84

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