Elan eSL Series, User Manual

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Chapter 2
eSL/eSLS Series (+ eSLZ000) User’s Manual Architecture
••••
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2.3.7 Immediate Addressing
A 16-bit program address is contained in the 16 LSBs of a 2-word instruction.
Example: CALL label and JMP label
Absolute Address
ROM Space
0
65535
OP
Figure 2-10 Immediate Addressing
2.3.8 Relative Program Addressing
Program execution continues at Address PC + 1. The offset is
contained in the instruction word. Short conditional branch instructions can
only get to locations –256 to 255 from the current address. However, Long
Branch instructions can reach the entire program memory from every location.
NOTE
Long range condition branch can reach from 0 to 65,535, but it needs two-word
instructions.
Program Counter
ROM Space
0
65535
+
Offset address OP
Figure 2-11 Relative Program Addressing