Subj:	Re: DTR1


Date:	95-12-17 12:15:38 EST


From:	DauphinTim


To:	PDC ChrisD


Sent on:	America Online (using WAOL 2.5)





Pinouts for DTR-1 HDD/Floppy Port





This port contains both a full IDE connector and a full floppy disk


connector.  There is some functional overlap between the two and


some pins are shared.  However, the only thing keeping both from


being attached via a single connector is that doing so generates


too much line noise.  They they begin to interfere with one


another.





Remember, external hard drives connected through this port are


Drive D on the same controller as the internal HDD (drive C). 


Floppy drives are drive A.





 Top Row (Right to Left)





  1   Reset - 


  3   XT Bus Data Bit 7


  5   XT Bus Data Bit 6


  7   XT Bus Data Bit 5


  9   XT Bus Data Bit 4


  11  XT Bus Data Bit 3


  13  XT Bus Data Bit 2


  15  XT Bus Data Bit 1


  17  XT Bus Data Bit 0


  19  Ground


  21  Drive Select 0 -


  23  I/O Write -


  25  I/O  Read -


  27  I/O CH Ready


  29  Write Gate -


  31  IRQ 14


  33  PC Address Bit 1


  35  PC Address Bit 0


  37  (Hard Drive) Chip Select 0 -


  39  Hard Drive LED


  41  5 volt source


  43  Ground


  45  Write Protect -


  47  (Floppy) Head Select


  49  (Floppy) Density Select








 Bottom Row (Right to Left)





  2   Ground


  4   AT Bus Data Bit 8


  6   AT Bus Data Bit 9


  8   AT Bus Data Bit 10


  10  AT Bus Data Bit 11


  12  AT Bus Data Bit 12


  14  AT Bus Data Bit 13


  16  AT Bus Data Bit 14


  18  AT Bus Data Bit 15


  20  (Floppy) Index  -


  22  (Floppy) Motor Select 0 -


  24  (Floppy) Direction -


  26  Step -


  28  (Floppy) Write Data -


  30  (Floppy) Track 0 -


  32  I/O Chip Select, 16 bit -


  34  P Diag -


  36  PC Address Bit 2


  38  Chip Select 1 -


  40  Ground


  42  5 volt source


  46  Ext. Disk Drive Power


  48  Read Data -


  50  Disk Change -


  52  Ext. Disk Drive Power