Atari 400 Technical Reference Manual page 529

Mixing Graphics Modes, cont.
II. PROCEDURE TO SET UP SCREEN IN MIXED MODES, cont.:
5. Convert all bytes to decimal.
example: Bvte (HEX)
DEC
LMS 46 70
Mode 1
06 6
Mode 7
aD
13
Mode 2 07
7
6. Execute a graphics calIon the computer using the max RAM
mo de
(+
16) •
example: GRAPHICS 7
+
16
7. PEEK the Display List pointer and use it to calculate a
variable labelled "START".
example: START
PEEK(560)
+
PEEK(561)
*
256
+
4
8. If the max RAM mode is at the top of the screen, then skip
this step: Poke the LMS byte to location START-I.
example: POKE START-l,70
9. Every mode line requires a mode byte in the Display List in
the same order as the mode lines appear on the screen. The
mode bytes must be POKED into the Display List at location
START
+
offset, where offset mode line
U.
Example: MODE LINE
II
POKE INSTRUCTION
2 POKE START
+
2 , 6
3
POKE START
+
3 , 6
MODE 1 4 POKE START
+
4 , 6
5 POKE START +
5 , 6
6 POKE START
+
6 , 6
MODE 7 see note for mode 7 (max RAM mode)
MODE 2 63 POKE START
+
63,7
64 POKE START
+
64,7
NOTE: ,The Display List will already be correct for the max RAM
mode,
~herefore
its mode bytes do not need to be POKEd.
B
-4-