ST6208C/ST6209C/ST6210C/ST6220C
9.3 INSTRUCTION SET
The ST6 offers a set of 40 basic instructions
which, when combined with nine addressing
modes, yield 244 usable opcodes. They can be di-
vided into six different types: load/store, arithme-
tic/logic, conditional branch, control instructions,
jump/call, and bit manipulation. The following par-
agraphs describe the different types.
Load & Store. These instructions use one, two or
three bytes depending on the addressing mode.
For LOAD, one operand is the Accumulator and
the other operand is obtained from data memory
using one of the addressing modes.
For Load Immediate, one operand can be any of
the 256 data space bytes while the other is always
immediate data.
All the instructions belonging to a given type are
presented in individual tables.
Table 17. Load & Store Instructions
Flags
Instruction
LD A, X
Addressing Mode
Short Direct
Bytes
Cycles
Z
∆
∆
∆
∆
∆
∆
∆
∆
∆
∆
∆
∆
∆
∆
∆
*
C
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
1
1
1
1
1
1
1
1
2
2
1
1
1
1
2
3
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
LD A, Y
LD A, V
LD A, W
LD X, A
LD Y, A
Short Direct
Short Direct
Short Direct
Short Direct
Short Direct
Short Direct
Short Direct
Direct
LD V, A
LD W, A
LD A, rr
LD rr, A
Direct
LD A, (X)
LD A, (Y)
LD (X), A
LD (Y), A
LDI A, #N
LDI rr, #N
Indirect
Indirect
Indirect
Indirect
Immediate
Immediate
Legend:
X, Y Index Registers,
V, W Short Direct Registers
#
rr
∆
*
Immediate data (stored in ROM memory)
Data space register
Affected
Not Affected
57/104
1
STMICROELECTRONICS [ ST ]
