Before getting to the bad stuff (the bugs), here are some goodies about ACTION! which we would like to pass on to you:
A magazine article titled "Lights, Camera, Action!" (by Dave Plotkin) which appeared in the July 1984 issue of ANTIC featured a set of routines to facilitate writing ACTION!-based interrupt handlers.
The article gave the listings for two routines (more properly, two DEFINEs) named "SaveTemps" and "GetTemps". These routines are adequate only if no math beyond addition and subtraction is performed in the interrupt service routine. The following versions of these two routines will work properly in the more general case:
Make the following DEFINEs in your program before you declare your interrupt routine (comments may be omitted-they exist only for clarification):
DEFINE SaveTemps=[
$A2 $07 ; LDX #7
$B5 $C0 ; LOOP LDA $C0,X
$48 ; PHA
$B5 $A0 ; LDA $A0,X
$48 ; PHA
$B5 $80 ; LDA $80,X
$48 ; PHA
$B5 $A8 ; LDA $A8,X
$48 ; PHA
$CA ; DEX
$10 $F1 ; BPL LOOP
$A5 $D3 ; LDA $D3
$48 ; PHA
]
DEFINE GetTemps=[
$68 ; PLA
$85 $D3 ; STA $D3
$A2 $00 ; LDX #0
$68 ; LOOP PLA
$95 $A8 ; STA $A8,X
$68 ; PLA
$95 $80 ; STA $80,X
$68 ; PLA
$95 $A0 ; STA $A0,X
$68 ; PLA
$95 $C0 ; STA $C0,X
$E8 ; INX
$E0 $08 ; CPX #8
$D0 $EF ; BNE LOOP
]"
Use these routines inside your interrupt routine as follows:
PROC InterruptRoutine()
; Local declarations, if any.
BYTE a, b, c, etc.
; First line of code within
; procedure SaveTemps
... ; Your interrupt
; code goes here.
GetTemps ; Last line of code
; within procedure.
[$6C OldVBI] ; A special way to
; end for VBIs- see
; below.
For example, the following program will set up the routine ChangeColor as a vertical blank interrupt routine (hit the START key to exit the program):
DEFINE SaveTemps=
[ $A2 $07 $B5 $C0 $48
$B5 $A0 $48 $B5 $80
$48 $B5 $A8 $48 $CA
$10 $F1 $A5 $D3 $48 ]
DEFINE GetTemps=
[ $68 $85 $D3 $A2 $00 $68
$95 $A8 $68 $95 $80 $68
$95 $A0 $68 $95 $C0 $E8
$E0 $08 $D0 $EF ]
CARD OldVBI ; Will hold previous
; contents of vertical
; blank interrupt
; vector.
; This procedure will change the background color to random values.
; The main routine will set up this code to operate during the
; deferred vertical blank interrupt.
PROC ChangeColor()
BYTE hue, lum
SaveTemps
hue = Rand( 16 )
lum = Rand( 16 )
SetColor(2,hue,lum)
GetTemps
[ $6C OldVBI ] ; Vertical blank
; interrupts must end
; like this ($6C is a
; 6502 indirect jump
; instruction).
PROC Test() ; Main routine
BYTE critic=$42, ; Critical I/O flag
console=$D01F ; Console key
; hardware location
CARD VBIvec=$224 ; Deferred vertical
; blank interrupt vector
; You must install a VBI routine like this:
critic = 1 OldVBI = VBIvec
VBIvec = ChangeColor
critic = 0
; ChangeColor is now running as the vertical blank interrupt
; routine-- since our mainline code has nothing more to do,
; we just go into a loop waiting for the START key to be
; pressed.
WHILE console&1
DO
OD
; Now turn off the VBI routine.
critic = 1
VBIvec = OldVBI
critic = 0
RETURN
This method of saving and restoring ACTION zero page variables may also be used to write BASIC machine language subroutines in ACTION! Your main ACTION routine should then have SaveTemps as the first executable line, and GetTemps as the last executable line before the RETURN statement.
The following is a list of all bugs we currently know exist in the ACTION! cartridge. We list these bugs separately from those in the RunTime library and/or the PAD disk or ToolKit, which occur in following pages. Each bug is described in detail and, when possible, bug fixes are given. Many of these bugs deal only with specific versions of ACTION!. To find out which version of ACTION! you own, type the following from the ACTION! monitor: ?$B000 [RETURN] Below is an actual copy of what printed following that command for one of our cartridges. 45055,$B000 = 0 $0730 48 1840 ^ To find out the version number, look at the character to the right of the equals sign (here printed with a caret under it). The "0" in this case implies that the cartridge is version 3.0. If yours has a "6", you own version 3.6, etc. As of the date of this bug sheet, the current cartridge version is 3.6.
; Beginning of program --
; First, declare TYPEs
TYPE IOCB =
[
BYTE Id, Devnum,
Command, Status
]
; Then, if desired,
; change offset
SET $B5 = $1000
; example: offset=4096
t = a(i) ; t is an INTEGER
...
ELSEIF t=0 THEN ...
This works properly.
X Close( 1 ) [RETURN]
You can then erase the file which caused the error.
TYPE REC=[...]
...
PROC Test( BYTE x, REC POINTER p )
Affects: All versions
Fix: Omit the comma in the argument list for the PROC/FUNC, as in:
PROC Test( BYTE x
REC POINTER p )
As this is just a temporary fix, it may not work in future versions, but the correct declaration (with the comma) will.
R* [[RETURN]
Affects: All versions
Fix: Don't do it! If you do type that command, hit [RESET]
BYTE ARRAY Paddle(4) = 624
; Contributed by Michael Ross
PROC SoundOff()
BYTE AudCtl = $D208,
SSKCtl = $232,
SKCtl = $D20F
SSKCtl = 3
SKCtl = 3
AudCtl = 0
SndRst()
RETURN
MoveBlock( rec.addr1,
rec.addr2, length )
Affects: Versions 3.0 to 3.5
Fix: Assign the TYPE field to a temporary variable and pass that as a parameter:
temp1 = rec.addr1
temp2 = rec.addr2
MoveBlock(temp1,temp2,length)
; Copyright (c) 1983 by
; Action Computer Services
;
; Permission is granted to duplicate and/or distribute
; the contents of this file to ACTION! users. Copies of
; this file may not be sold or used for monetary gain.
PROC DivI=*()
[$20 $A06C $85 $86 $A2 $10
$26 $82 $26 $83 $26 $86 $26
$87 $38 $A5 $86 $E5 $84 $A8
$A5 $87 $E5 $85 $90 $04 $85
$87 $84 $86 $CA $D0 $E5 $A5
$82 $2A $26 $83 $A6 $83
$4C $A032]
PROC RemI=*()
[$20 DivI $86A5 $87A6 $60]
SET $4EA=DivI
SET $4EC=RemI
DO
...
UNTIL a>0 AND b=3
OD
Affects: Versions 3.0 and 3.1
Fix: Assign the expression to a temporary variable and test that variable, instead:
DO
...
temp = a>0 AND b=3
UNTIL temp
OD
BYTE bank = $D500
; This declares the variable
; 'bank' to reside at $D500.
bank = 0 ; This must be the
; first executable statement.
BYTE RTS=[$60]
; This MUST be the first line in your program,
; aside from comments and SET commands.
PROC CIO = $E456() []
; An empty code block!
SET $E=$491^