dudek@utai.UUCP (Gregory Dudek) (06/26/85)
....
A plea for assistance... I've been working on a program
for the Apple II that uses the 80-column card, and am having
a bad time trying to get it going on the IIe. The
program does cursor addressing by sending characters to the card
via the "Pascal entry" at location $c9aa. This works fine on
(most cards) on the II+. On the IIe, however, all sorts of
extra weird characters are produced and the addressing is not always
accurate.
I've tried poring over the IIe 80-column card ROM listings to no avail.
Can anybody help me? I init the card (in slot 3) by jumping
to $c300.
*ANY* help would be much appreciated. Please don't hold off
responding because you think someone else will -- I don't count
on a big response.
Is there a standard initialization entry point other than $c300
for use by pascal?
Thanks, Greg Dudek
UUCP {ihnp4 utzoo decwrl uw-beaver}!utcsri![utai!]dudek
CSNet dudek@toronto
ARPA dudek%toronto@csnet-relayags@pucc-h (Dave Seaman) (06/29/85)
In article <583@utai.UUCP> dudek@utai.UUCP (Gregory Dudek) writes: >.... > A plea for assistance... I've been working on a program >for the Apple II that uses the 80-column card, and am having >a bad time trying to get it going on the IIe. The >program does cursor addressing by sending characters to the card >via the "Pascal entry" at location $c9aa. This works fine on >(most cards) on the II+. On the IIe, however, all sorts of >extra weird characters are produced and the addressing is not always >accurate. > Can anybody help me? I init the card (in slot 3) by jumping >to $c300. The Pascal initialization entry is $C3xx, where xx is the value stored at $C30D. On an enhanced //e the value is $4A, meaning that the initialization entry JPINIT is located at $C34A. If you are using a different Apple II-series machine (such as an unenhanced //e), or if you use a non-Apple 80-column card, you will need to find the correct value for your machine. Note that the $C300 entry does BASIC initialization, and BASIC does not recognize cursor addressing. For completeness, the other Pascal entry points are described as follows in Apple's ROM listings (enhanced //e version): * Pascal 1.1 Firmware Protocol table: * * This table identifies this as an Apple //e 80 column * card. It points to the four routines available to * programs doing I/O using the Pascal 1.1 Firmware Protocol. * C30B:01 DFB $01 ;GENERIC SIGNATURE BYTE C30C:88 DFB $88 ;DEVICE SIGNATURE BYTE C30D:4A DFB #>JPINIT ;PASCAL INIT C30E:50 DFB #>JPREAD ;PASCAL READ C30F:56 DFB #>JPWRITE ;PASCAL WRITE C310:5C DFB #>JPSTAT ;PASCAL STATUS -- Dave Seaman ..!pur-ee!pucc-h:ags