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Re: Super Serial Card Question?

mdj wrote:

Michael J. Mahon wrote:



If you drop a $10 into the 6551 speed register, it runs at 115kbps.
Apparently, this is not well known, since someone sells a "turbo"
option daughterboard to achieve this speed, too.



Interesting. That's actually plenty of speed to deliver virtual disk
devices, as it's theoretically  faster than a disk ][ at that speed.
Wonder if anyone would be interested in such a driver for ProDOS...


I think there would be.


I use the Workstation card myself, as I've mentioned, which gives both
Appletalk compatibility and a 'fast' serial port as it uses the ACIA's
of the IIgs/macintosh rather than the 6551. Unfortunately this breaks
compatibility with any software that doesn't use the Apple firmware
interface, which also unfortunately, is most useful comms software :-(

Apple seemed to go through a period of shoddy I/O firmware. The Super
Serial was a shocker in this regard, and the original IIe 80-column
firmware was also pretty awful.


Most comm and terminal software was conceived of as having relatively
low performance requirements.  This was admittedly shortsighted, as
became clear when even slow interrupt-driven comm software could not
make use of the standard 80-column firmware because of slow scrolling
routines that were non-interruptible.

The 80-column firmware rev and interrupt improvements in the enhanced
ROMs came in time to be widely used, by essentially all applications.
But by the time that the weakness of the SSC firmware for high-speed
operation was clear, only comm programs cared, and they had already
worked around it, so no update was ever made.
packages had already worked around it, so


I'm surprised by the number of mentions of unenhanced IIe's on this
list. I haven't even seen one since about 1986! I guess a number of
people just used IIe's as replacement II+'s and never wanted for more.


Frankly, many users don't have much need for a 65C02, mousetext, and
the enhanced monitor ROM, nor do most applications.

-michael

Music synthesis for 8-bit Apple II's!
Home page:  http://members.aol.com/MJMahon/

"The wastebasket is our most important design
tool--and it is seriously underused."