Elan eSL Series, User Manual

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Chapter 2
eSL/eSLS Series (+ eSLZ000) User’s Manual Architecture
••••
33
2.5.4 Data Transfer Instruction
The Data Transfer instruction moves data from a source to a destination. It
provides indirect auto-increase or decrease mode for moving large block of data
around main memory. The following table lists the functions within the Data
Transfer instruction.
2.5.4.1 Data Transfer Instruction Description
Mnemonic Description
MOV Move from RHS
1
to LHS
2
IN Input from I/O
OUT Output to I/O
PUSH Push to TOS
POP Pop from TOS
3
1
RHS: Right hand side
;
2
LHS: Left hand side
;
3
TOS: Top of stack
MOV instruction provides the data transfer ability to move data from memory
to register (LOAD) or from register to memory (STORE). IN and OUT
instructions are capable of moving data via I/O space, while PUSH and POP
instructions provide a channel between register and stack (or I/O and stack).
There are two kind data memory mov instruction, one is 8-bit mov instruction,
user need to set BSR and 8-bit direct address to do the mov operation, the other
is 16-bit long mov instruction, user just need to set 16-bit direct address. Please
see the instruction table to understand the performance and space between this
two instructions.
2.5.4.2 Data Transfer Addressing Categories
As the eSL Series architecture are register based, the chips are powerful in
moving data from register to any space as demonstrated in the following table.
Source
Destinat’n
Register RAM Direct
RAM Indirect
(with Inc/Dec)
ROM Indirect
(with Inc/Dec)
I/O Space
(IN/OUT)
Stack
(PUSH/POP)
Immediate
Register Available Available Available Available Available Available Available
RAM Direct Available - - - - - -
RAM Indirect Available - - Available - - Available
I/O Space Available - - - - Available -
Stack Available - - - Available - -