Laptop User Manual

S3C2440A RISC MICROPROCESSOR THUMB INSTRUCTION SET
4-33
FORMAT 15: MULTIPLE LOAD/STORE
[7:0] Register List
[10:8] Base Register
[11] Load/Store Bit
0 = Store to memory
1 = Load from memory
15 0
1
14
10
10
13 12
11
Rlist
0 L
78
Rb
Figure 4-16. Format 15
OPERATION
These instructions allow multiple loading and storing of Lo registers. The THUMB assembler syntax is shown in
the following table.
Table 4-16. The Multiple Load/Store Instructions
L THUMB assembler ARM equivalent Description
0 STMIA Rb!, { Rlist } STMIA Rb!, { Rlist } Store the registers specified by Rlist,
starting at the base address in Rb. Write
back the new base address.
1 LDMIA Rb!, { Rlist } LDMIA Rb!, { Rlist } Load the registers specified by Rlist, starting
at the base address in Rb. Write back the
new base address.
INSTRUCTION CYCLE TIMES
All instructions in this format have an equivalent ARM instruction as shown in Table 4-16. The instruction cycle
times for the THUMB instruction are identical to that of the equivalent ARM instruction.
EXAMPLES
STMIA R0!, {R3-R7} ; Store the contents of registers R3-R7 starting
at the address specified in R0, incrementing the
addresses for each word. Write back the updated
value of R0.