HMS87C1808B Datasheet, PDF (38/99 Pages) List of Unclassifed Manufacturers – 8-BIT SINGLE-CHIP MICROCONTROLLERS

HMS87C1X04B/08B/16B
Y indexed direct page (8 bit offset) → dp+Y
This address value is the second byte (Operand) of command plus
the data of Y-register, which assigns Memory in Direct page.
This is same with above (2). Use Y register instead of X.
Y indexed absolute →!abs+Y
Sets the value of 16-bit absolute address plus Y-register data as
Memory. This addressing mode can specify memory in whole ar-
ea.
Example; Y=55_H
D500FA LDA !0FA00H+Y
3F35
JMP [35H]
35_H
36_H
~~
0E30A_H
~~
0FA00_H
0A
E3
NEXT
3F
35
~~ ^{2 jump to address 0E30AH}
~~
1
0F100_H
D5
0F101_H
00
0F102_H
FA
~~
0FA55_H
data
1
0FA00H+55H=0FA55H
~~
2
data → A
3
(6) Indirect Addressing
Direct page indirect → [dp]
Assigns data address to use for accomplishing command which
sets memory data (or pair memory) by Operand.
Also index can be used with Index register X,Y.
JMP, CALL
Example;
X indexed indirect → [dp+X]
Processes memory data as Data, assigned by 16-bit pair memory
which is determined by pair data [dp+X+1][dp+X] Operand plus
X-register data in Direct page.
ADC, AND, CMP, EOR, LDA, OR, SBC, STA
Example; X=10_H
1625
ADC
[25H+X]
35_H
05
36_H
E0
~~
0E005_H
data
~~
0FA00_H
16
25
~~ ^{2 0E005H}
1 25 + X(10) = 35H
~~
3 A + data + C → A
34
SEP. 2004 Ver 1.03