> Has anyone ever used the PIC16F877 to control a hard
> drive directly (ie. without 8255)?  Any comments, suggestions, problems?


_________

IDE on an Apple 2 (!!!!!!!!!!!!!!!!!) using 2 x 74HCT373 and some glue
logic.
It seems that ALL the circuitry would be replaceable by the PIC.
Notice that this works on "older" IDE drives but stopped working with newer
ones - he thinks for timing reasons.
Excellent proof of concept demo though.

    http://s.guillard.free.fr/Apple2IDE/Apple2IDE.htm


8051 with 8255 version.
This is just 3 x 8 bit ports to IDE drive plus 5 x 74HC04 inverters - 3 PIC
ports would serve as well.
He provides basic 8051 code but no FAT implementation.

        http://www.pjrc.com/tech/8051/ide/#schematic


Utterly superbulous IDE implementation resource
ATA specs
8051/8255 implementation.
C software
& *MUCH* more
    http://www.mp3projects.com/data.htm
    includes:

       d0791r4c.pdf - ATA-1 (IDE) Standard - Revision 4c
      d0948r4c.pdf - ATA-2 (EIDE or FastATA) Standard - Revision 4c
      d2008r7b.pdf - ATA-3 Standard - Revision 7b
      d1153r18.pdf - ATA/ATAPI-4 Standard - Revision 18
      d1321r3.pdf - ATA/ATAPI-5 Standard - Revision 3
      d1410r3.pdf - ATA/ATAPI-6 Standard - Revision 3
      d1532v3r0.pdf - ATA/ATAPI-7 Standard - Revision 0 - Vol 3
      atafaq.zip - ATA/ATA-1/ATA-2/IDE/EIDE/etc FAQ
      ya-ata.zip - Yet Another EIDE / Fast-ATA / ATA-2 FAQ
      ide-8255.zip - How to connect an IDE disk to a microcontroller using
an 8255
      ide-8051.zip - Info and complete c code on controlling an IDE drive
from an Intel 8051
      ide-pinouts.zip - Pinouts for a 44 Pin IDE Connector
      d1510rr0a.pdf - ATA/ATAPI Host Adaptor Standard
      d1226r7.pdf - Enhanced BIOS Services for Disk Drives - Revision 7
      allhiw.zip - How It Works

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