[Coco] Using DriveWire to write network software

[RETRO Innovations]

On 3/30/2017 5:44 PM, Mark D. Overholser wrote:
>
> I agree with this approach, to a point...
>
> With an Ethernet or WiFi connection, and a Flash Chip ( EEPROM ), you 
> could design a Network Bootable Device..
>
> An Ethernet device like the W5100 could Map its 16K of Buffers in to 
> unused Memory space on a 4K CoCo, ( or 4K Apple ][ ), and have a 
> fairly nice gaming experience..  Very Retro, and Modern..
As someone who has spent his life in networking, speed of conn for this 
kind of game is not your main concern, so tying up kilobytes of RAM in 
the Coco footprint to shave some speed off of comm is not worth the 
effort, IMHO.

But, I posit you can have your cake and eat it too:

$ff68:  emulated RS232 data port

$ff6a: indirect register for W5100
$ff6b: indirect reg for W5100

$ff70: config bits: bit 0 = 1 -> map W5100 into c000-dfff
$ff71: config bank: which W5100 bank maps into c000-dfff

Easy RS232 interface for the compatibility, indirect for the lightweight 
stuff, and mapped memory for the heavy stuff.  Choose your poison

Jim