INSTRUCTION SET

S3C84E5/C84E9/P84E9

 

 

LDC/LDE — Load Memory

LDC

dst,src

LDE

dst,src

Operation:

dst src

 

This instruction loads a byte from program or data memory into a working register or vice-versa. The

 

source values are unaffected. LDC refers to program memory and LDE to data memory. The

 

assembler makes "Irr" or "rr" values an even number for program memory and an odd number for

 

data memory.

Flags: No flags are affected.

Format:

1.

opc

dst

src

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

2.

opc

src

dst

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

3.

opc

dst

src

XS

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

4.

opc

src

dst

XS

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

5.

opc

dst

src

XLL

XLH

 

 

 

 

 

 

 

6.

opc

src

dst

XLL

XLH

 

 

 

 

 

7.

opc

dst 0000

DAL

DAH

 

 

 

 

 

8.

opc

src 0000

DAL

DAH

 

 

 

 

 

9.

opc

dst 0001

DAL

DAH

 

 

 

 

 

10.

opc

src 0001

DAL

DAH

NOTES:

Bytes

Cycles

Opcode

Addr Mode

 

 

(Hex)

dst

src

2

10

C3

r

Irr

2

10

D3

Irr

r

3

12

E7

r

XS [rr]

3

12

F7

XS [rr]

r

4

14

A7

r

XL [rr]

4

14

B7

XL [rr]

r

4

14

A7

r

DA

4

14

B7

DA

r

4

14

A7

r

DA

4

14

B7

DA

r

1.The source (src) or the working register pair [rr] for formats 5 and 6 cannot use the register pair 0 –1.

2.For the formats 3 and 4, the destination "XS [rr]" and the source address "XS [rr]" are both one byte.

3.For the formats 5 and 6, the destination "XL [rr] and the source address "XL [rr]" are both two bytes.

4.The DA and the r source values for the formats 7 and 8 are used to address program memory. The second set of values, used in the formats 9 and 10, are used to address data memory.

5.LDE instruction can be used to read/write the data of 64-Kbyte data memory.

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Image 179
Samsung S3C84E5 user manual LDC/LDE Load Memory, Ldc, Lde, Bytes Cycles Opcode Addr Mode Hex Dst Src