[Home]History of EPP

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Revision 3 . . May 6, 2006 4:00 am by Fenn [deleted because this module has been implemented]
Revision 2 . . November 13, 2005 7:20 pm by Fenn

Difference (from prior major revision) (no other diffs)

Changed: 1,18c1
EPP HAL Module

Some thoughts for implementing the IEEE 1284 Enhanced Parallel Port protocol in HAL.

Here is a description of the EPP protocol: http://www.fapo.com/eppmode.htm

This protocol is used by Pico Systems' PPMC, and the (as yet nameless) Sanyo P5 BLDC servo driver board, being developed by various EMC users here: http://forums.donniebarnes.com/viewforum.php?f=16

And, fenn has been talking about building something like that for a while now; we'll see if he ever gets around to it.

Hal representation

How do you represent a serial communications scheme in a user interface that is primarily parallel?

1) hard-coded protocol, with n*hal_u32 inputs/outputs for encoder counts and separate hal_bit i/o for digital io

2)flexible protocol, with registers for each byte transmitted represented by hal_u8 pins (jmk dislikes this because it would be extra confusing, and useless for anyone but a driver developer who already knows how to write code anyway)

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