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Re: apple 2 usb
- Subject: Re: apple 2 usb
- From: "David Wilson" <mcs6502@gmail.com>
- Date: 29 Dec 2005 04:46:35 -0800
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bob@bob.us wrote:
> how hard would it be to create a usb card for the 2? even just a gs usb
> card?
It is harder than you might think. A USB host has to do a lot more work
than a USB target - the USB protocol was written to make simple devices
like mice cheap to make. Also, the Apple II has never had hot pluggable
devices (SCSI, ADB, Smartport etc all enumerate the devices once at
power-up/boot). Finally, the standards for mouse cards and disk cards
(for example) use conflicting ROM ID locations making a card that can
support both difficult to design using standard interfaces.
It certainly could be done for the IIgs but you would need to write
GS/OS drivers for all possible USB devices (mice, keyboards, mass
storage etc) as well as the code for an embedded microprocessor on the
card to run the USB protocol.
I will be impressed if anyone (or a group) manage to do this.