Disable CoCo 1/2 Extended Color BASIC

[zephyr]

The following routines can be used to disable Extended Color BASIC on a CoCo 1 or 2. The machine will restart in Color BASIC mode only. These routines are useful if you have written your own program, and would like to test it on an unexpanded CoCo.

Code: Select all

10 'ECB DISABLE V1.0
20 'FOR THE TANDY COCO 1 AND 2
30 'BY STEVE EVANS (ZEPHYR)
40 '
50 PCLEAR4:S=3584:B=0
60 FOR X=S TO S+60:READ A$:A=VAL("&H"+A$):POKE X,A:B=B+A:NEXT
70 IF B=7946 THEN EXEC S
80 PRINT"ERROR IN DATA LINES.":END
90 DATA 8E,A0,E,CE,E,3D,A6,80,A7,C0,8C,A0,CB,26,F7,F6,A0,7A,8E,E,B2,3A,CC,8E,7E,A7,80,E7,C0,DC
100 DATA 74,ED,81,CC,20,A,ED,84,7F,E,44,8E,A0,D5,AF,C4,1A,50,F,71,8E,44,4B,BC,C0,0,26,3,7F,FF,40

Code: Select all

10 'ECB DISABLE V1.0B
20 'FOR THE TANDY COCO 1 AND 2
30 'BY STEVE EVANS (ZEPHYR)
40 '
50 PCLEAR4:D=&HC000:Z=&HE02
60 POKE Z-2,&H1A:POKE Z-1,&H50
70 FOR X=&HA00E TO &HA0CA:POKE Z,PEEK(X):Z=Z+1:NEXT
80 O=&HE77+PEEK(&HE6E)
90 POKEO,&H8E:POKEO+1,PEEK(&H74):POKEO+2,PEEK(&H75):POKEO+3,&H20:POKEO+4,&HA
100 POKE Z,&H7E:POKE Z+1,&HA0:POKE Z+2,&HD5
110 IF PEEK(D)+PEEK(D+1)=143 THEN POKE&HFF40,0
120 POKE&HE09,0:POKE&H71,0:EXEC&HE00

[zephyr]

The attached program will disable Extended Color BASIC on a CoCo 3.