marty1@houem.UUCP (M.BRILLIANT) (11/01/85)
I am using a Model III and a Model 4, both cassette systems. As such, the Model 4 runs only in Model III mode. The Model III is being used as an intelligent terminal, but I would like a bigger display if I could get it cheap. With disk drives and the right DOS, the Model 4 would do certain things the Model III can not do, such as display 24 lines of 80 columns each, and address 64K of RAM. I do not know how this is done. I don't think it really depends on having disks; more likely, it depends on sending the right flags to the right ports. Can anybody tell me what the trick is? Alternatively, there is a diskware product called Supermod4, for a Model 4 running a Model III DOS, that enables the 80x24 screen but still allows ROM+48KRAM addressing. Can this product be adapted to cassette use? M. B. Brilliant houem!marty1 39 McCampbell Road Holmdel, NJ 07733 (201)-946-8147 AT&T-BL Holmdel, NJ (201)-949-1858
sob@neuro1.UUCP (Stan Barber) (11/09/85)
Well, you are right that you can push info out to certain ports to make
things happen. And it does not require disks to do this, but it is
hard to use 64K of ram that is empty. Once you do the ROM swapout, there
is no way to load the ram with anything. The boot code only works with
the disk drives on the standard Model 4 although I understand that is
different on the 4P (and may be on the new 4D).
You cannot use the 4 in III mode with the 80x24 screen without a special
driver to cause all the video mapping to happen right. Real tricky. I know
come word processing software that does this (LeScript, I belive), but
otherwise, hard to do.
Sorry this is such a downer.
--
Stan uucp:{ihnp4!shell,rice}!neuro1!sob Opinions expressed
Olan ARPA:sob@rice.arpa here are ONLY mine &
Barber CIS:71565,623 BBS:(713)660-9262 noone else's.