Modify Address Register - Analog Devices adsp-2100 Manual

Syntax:
MODIFY
Example:
MODIFY (I1, M1);
Description:
Add the selected M register (M
(I ), then process the modified address through the modulus logic with
m
buffer length as determined by the L register corresponding to the
selected I register (L
in the selected I register. The I register is modified as if an indexed
memory address were taking place, but no actual memory data transfer
occurs. For linear (i.e. non-circular) indirect addressing, the L register
corresponding to the I register used must be set to zero.
The selection of the I and M registers is constrained to registers within the
same Data Address Generator: selection of I0-I3 in Data Address
Generator #1 constrains selection of the M registers to M0-M3. Similarly,
selection of I4-I7 constrains the M registers to M4-M7.
Status Generated:
Instruction Format:
Modify Address Register, Instruction Type 21:
23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
0 0 0 0 1
G specifies which Data Address Generator is selected. The I and M
registers specified must be from the same DAG, separated by the gray bar
above. I specifies the I register (depends on which DAG is selected by the
G bit). M specifies the M register (depends on which DAG is selected by
the G bit).

MODIFY ADDRESS REGISTER

( I0 ,
I1
I2
I3
I4
I5
I6
I7
), and store the resulting address pointer calculation
m
None affected.
0 0 1 0 0 0
M0 ) ;
M1
M2
M3
M4
M5
M6
M7
) to the selected I register
n
0 0 0 0 0 0 0 0 G
MISC
15
I M
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