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HP Forum Archive 20

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HP 9127A with 85/87
Message #1 Posted by David Ramsey on 6 June 2011, 4:04 p.m.

Can the HP 9127A HP-IB 5.25" floppy drive be used with the HP-85/87 computers? Empirical evidence would suggest not...perhaps it uses a different command set. But if anyone knows for sure...

      
Re: HP 9127A with 85/87
Message #2 Posted by Juergen Keller on 6 June 2011, 5:11 p.m.,
in response to message #1 by David Ramsey

You can find the manual here. I quickly browsed through it but I didn't found a reference to Series 80 computers. The 9127A uses the SS/80 protocol so my guess is that it might work. However, I would recommend a 3.5" floppy drive, they are much more convenient.

            
Re: HP 9127A with 85/87
Message #3 Posted by David Ramsey on 6 June 2011, 8:21 p.m.,
in response to message #2 by Juergen Keller

I have a 9121 3.5" diskette drive, this one was just for...I dunno...completeness. Can't seem to get the 85/87 to "see" it, though. I have the manual for the drive and will check some more. With the drive address set to "4" and the computers at "7", I thought:

MASS STORAGE IS ":D704"

would let me use it. Nope...

                  
Re: HP 9127A with 85/87
Message #4 Posted by Juergen Keller on 7 June 2011, 2:44 a.m.,
in response to message #3 by David Ramsey

According to Series 80 Tips, drives using the Amigo protocol (like the 9121) should work with an HP-85. If you have an HP-85A you need the Mass Storage and I/O ROM. For drives using the SS/80 protocol (like the 9127A) you need the EMS ROM.

The device address 704 seems to be correct. Do you know if the drive and the HP-IB interface are working (i.e., did you use them successfully with other devices and other computers, respectively)?

                        
Re: HP 9127A with 85/87
Message #5 Posted by David Ramsey on 7 June 2011, 11:37 a.m.,
in response to message #4 by Juergen Keller

The 9121 works perfectly with both computers. In fact they can both be connected at the same time since the 87's "controller" switch is turned off.

I don't have the Extended Mass Storage ROM for the 87, though. (And there's no way to get the drive to work with an 85A, dang.)

If anyone out there has an EMS ROM for the 87, I have numerous other 87 ROMs, ROM drawers, BCD and serial interfaces, etc. that I'd be happy to trade.


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