From 6034aa039dcb283db6b68a6476205b886a481579 Mon Sep 17 00:00:00 2001 From: mgcaret Date: Thu, 16 Mar 2017 20:12:41 -0700 Subject: [PATCH] Update README.md --- rom5x/README.md | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/rom5x/README.md b/rom5x/README.md index c1bd951..a56bd2a 100644 --- a/rom5x/README.md +++ b/rom5x/README.md @@ -2,6 +2,9 @@ ## PRELIMINARY, NOT EXTENSIVELY TESTED +*I have not tested this with the A2Heaven RAM card yet, but all of the other +functionality definitely works. + This is ROM 5X, providing the ROM 4X functionality to the Apple IIc Plus ROM version 5. @@ -16,11 +19,13 @@ presumably so that multiple beeps are distinct from each other. I patch the JSR WAIT to be STA $C028, which switches to the other bank. The code in the other bank checks the accumulator and for two values calls -either reset5x or boot5x, and for any other value executes the WAIT (assuming -that we got there from BEEP1) and returns back to BEEP1. +either reset5x or boot5x, for a third value ($40 loaded by BEEP1) does the +classic Apple II "air raid" beep sound, and for any other value executes the WAIT +(assuming that we got there from BEEP1) and returns back to BEEP1. -Then, in only 6 bytes I can create two entry points that load the value into -A that we need for the reset or boot routines, and then jump to the above patch. +Then, in only 6 bytes I can create two entry points that load the right values +into the A register that we need for the reset or boot routines, and then jump +to the above patch. ## Options