Jameco Electronics 3000 User Manual
248
Rabbit 3000 Microprocessor
Spreadsheet Conventions
ALTD (“A” Column) Symbol Key
IOI and IOE (“I” Column) Symbol Key
Flag Register Key
Flag
Description
f
ALTD selects alternate flags
fr
ALTD selects alternate flags and register
r
ALTD selects alternate register
s
ALTD operation is a special case
Flag
Description
b
IOI and IOE affect source and destination
d
IOI and IOE affect destination
s
IOI and IOE affect source
S
Z L/V
*
* The L/V (logical/overflow) flag serves a dual purpose—
L/V is set to 1 for logical operations if any of the four
most significant bits of the result are 1, and L/V is reset to
0 if all four of the most significant bits of the result are 0.
most significant bits of the result are 1, and L/V is reset to
0 if all four of the most significant bits of the result are 0.
C
Description
*
Sign flag affected
-
Sign flag not affected
*
Zero flag affected
-
Zero flag not affected
L
LV flag contains logical check result
V
LV flag contains arithmetic overflow result
0
LV flag is cleared
*
LV flag is affected
*
Carry flag is affected
-
Carry flag is not affected
0
Carry flag is cleared
1
Carry flag is set