[rescue] Parallel ports [was Re: Slightly OT: ?Bad Cap Saga]

Geoffrey S. Mendelson gsm at mendelson.com
Thu Aug 21 02:39:45 CDT 2008

On Thu, Aug 21, 2008 at 02:22:11AM -0500, Jonathan C. Patschke wrote:
>Particularly irritating is that the parallel port hardware is still
>present on a great many of the "southbridge" I/O controllers.  It's just
>disabled in a configuration register and not brought out to a physical
>port.  At the very least, it'd be nice for there to be a header somewhere
>(which would cost less than a penny, provided there's sufficient board
>space), so that the end-user could have a parallel port merely by
>connecting a cable.

Would they? Then it actually has to work, be tested and the drivers 
kept up to date. Just because the chip can do it, doesn't mean that
it will do it and that the old software will support it.

For example, I'm sitting at an old Macintosh with an IDE I/O controller
chip that will happily read data with DMA at 66mHz, unfortunately
the data does not always wind up in the right place. :-(

For a while Apple included code in the operating system to check for
the chip and limit it to 33mHz, but since they never sold any of these
computers with devices that included 66mHz DMA, they said "screw it"
and stopped. 


Geoffrey S. Mendelson, Jerusalem, Israel gsm at mendelson.com  N3OWJ/4X1GM

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