273
Data Movement Instructions
Section 5-18
5-18-5 DATA EXCHANGE – XCHG(73)
Limitations
DM 6144 to DM 6655 cannot be used for E1 or E2.
Description
When the execution condition is OFF, XCHG(73) is not executed. When the
execution condition is ON, XCHG(73) exchanges the content of E1 and E2.
If you want to exchange content of blocks whose size is greater than 1 word,
use work words as an intermediate buffer to hold one of the blocks using
XFER(70) three times.
Flags
ER:
Indirectly addressed EM/DM word is non-existent.
(Content of
*
EM/
*
DM word is not BCD, or the EM/DM area boundary
has been exceeded.)
5-18-6 SINGLE WORD DISTRIBUTE – DIST(80)
Limitations
C must be BCD.
DM 6144 to DM 6655 cannot be used for DBs or C.
Description
DIST(80) can be used for single-word distribution or for a stack operation
depending on the content of the control word, C.
Single-word Distribution
When bits 12 to 15 of C=0 to 8, DIST(80) can be used for a single word dis-
tribute operation. The entire contents of C specifies an offset, Of.
When the execution condition is OFF, DIST(80) is not executed. When the
execution condition is ON, DIST(80) copies the content of S to DBs+Of, i.e.,
Of is added to DBs to determine the destination word.
Note
DBs and DBs+Of must be in the same data area and cannot be between
DM 6144 and DM 6655.
Example
The following example shows how to use DIST(80) to copy #00FF to HR 10 +
Of. The content of LR 10 is #3005, so #00FF is copied to HR 15 (HR 10 + 5)
when IR 00000 is ON.
E1
:
Exchange word 1
IR, SR, AR, DM, EM, HR, TIM/CNT, LR
E2
: Exchange word 2
IR, SR, AR, DM, EM, HR, TIM/CNT, LR
Ladder Symbols
Operand Data Areas
XCHG(73)
E1
E2
@XCHG(73)
E1
E2
E2
E1
S
:
Source data
IR, SR, AR, DM, EM, HR, TIM/CNT, LR, #
DBs
:
Destination base word
IR, SR, AR, DM, EM, HR, TIM/CNT, LR
Ladder Symbols
Operand Data Areas
C
:
Control word (BCD)
IR, SR, AR, DM, EM, HR, TIM/CNT, LR, #
DIST(80)
S
DBs
C
@DIST(80)
S
DBs
C
