[comp.sys.ibm.pc] Shugart floppy disk bus

zotog@sersun0.essex.ac.uk (02/27/90)

To any body interested here are the pin assignment for a standard 34-way floppy
disk bus. (Taken from a Computer Engineer's pocket book )




	this		1||2  not connected, reserved, or 0V
	side		3||4  IN USE or HEAD LOAD, NOT(HLD)
			 ==   NOTCH
			5||6  DRIVE SELECT 4, NOT(DS4)
			7||8  INDEX, NOT(IP)
			9||10 DRIVE SELECT 1, NOT(DS1)
	GND	       11||12 DRIVE SELECT 2, NOT(DS2)
		       13||14 DRIVE SELECT 3, NOT(DS3)
	or	       15||16 MOTOR ON, NOT(MOTOR)
		       17||18 DIRECTION SELECT, DIRC
		       19||20 STEP, STEP
	0V	       21||22 WRITE DATA, WD
		       23||24 WRITE GATE, WG
		       25||26 TRACK 00, NOT(TR00)
		       27||28 WRITE PROTECTED, NOT(WPRT)
		       29||30 READ DATA, RDATA
		       31||32 SIDE SELECT, SIDE
		       33||34 READY, NOT(RDY)



If any one is interested I could send more info abouteach pin.
By the way the above pin out applies and to the 3.5 drives with 34 pin connector.

amichiel@rodan.acs.syr.edu (Allen J Michielsen) (02/28/90)

In article <3257@servax0.essex.ac.uk> zotog@sersun0.essex.ac.uk writes:
>
>
>here are the pin assignment for a standard 34-way floppy
>above pin out applies and to the 3.5 drives with 34 pin connector.

Just so we don't have to hear this later, the key word above is
standard.  Shugart, and everybody else made full ht, 1/2 ht, or 3.5" drives
that use the same comnnector, (34 header, or 34 Pin) which were NOT
standard.  They were/are used in PCjr's, apples, macs, and SOME of the
(more) oddball pc clones. (I believe eagle may fall in this group but....).

I know of no way to tell from looking at a particular drive if it is
oddball, serial, or non standard.  The above info DOES however cover probably
over 90% of computer drives currently in use & is veru good & helpful.

al

Ralf.Brown@B.GP.CS.CMU.EDU (02/28/90)

In article <2261@rodan.acs.syr.edu>, amichiel@rodan.acs.syr.edu (Allen J Michielsen) wrote:
}standard.  Shugart, and everybody else made full ht, 1/2 ht, or 3.5" drives
}that use the same comnnector, (34 header, or 34 Pin) which were NOT
}standard.  They were/are used in PCjr's, apples, macs, and SOME of the
}(more) oddball pc clones. (I believe eagle may fall in this group but....).

Not the Eagle PC I had.  I put one of its floppy drives into the AT clone I
bought to replace it.  All I had to do was mask pin 34 (the XT vs AT
difference in pin 34's meaning....).
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