IDEC MICROSmart FC6A-C16K1CE, Руководство по связи, Страница: 89 / 252

FC6A S
ERIES
M
ICRO
S
MART
A
LL
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IN
-O
NE
T
YPE
C
OMMUNICATION
M
ANUAL
FC9Y-B1730 5-13
5: U
SER
C
OMMUNICATION
I
NSTRUCTIONS
Delimiter
A delimiter for the data register in the receive format can be assigned. Using a delimiter, incoming data of variable length can be
received and stored to data registers.
Note: Delimiters for data registers can be used in the receive format of RXD instructions only.
Designating Constant as Start Delimiter
A start delimiter can be programmed at the first byte in the receive format of a RXD instruction; the FC6A Series MicroSmart will
recognize the beginning of valid communication, although a RXD instruction without a start delimiter can also be executed.
When a constant value is designated at the first byte of source device S1, the one-byte data serves as a start delimiter to start the
processing of the received data.
A maximum of five instructions each of RXD1 through RXD3 with different start delimiters can be executed at the same time.
When the first byte of the incoming data matches the start delimiter of a RXD instruction, the received data is processed and
stored according to the receive format specified in the RXD instruction. If the first byte of the incoming data does not match the
start delimiter of any RXD instruction that is executed, the FC6A Series MicroSmart discards the incoming data and waits for the
next communication.
When a RXD instruction without a start delimiter is executed, any incoming data is processed continuously according to the receive
format. Only one instruction each of RXD1 through RXD3 without a start delimiter can be executed at a time. If start inputs to two
or more RXD instructions without a start delimiter are turned on simultaneously, the one at the smallest address is executed and
the corresponding completion output is turned on.
Example:
(1) When a RXD instruction without a start delimiter is executed
(2) When RXD instructions with start delimiters STX (02h) and ENQ (05h) are executed
Delimiter How the incoming data is stored to data registers
Designated
The incoming data is stored to data registers until all the data specified with receive digits, conversion type, and repeat
is processed or the specified delimiter is received.
No delimiter
The incoming data is stored to data registers until all the data specified with receive digits, conversion type, and repeat
is processed.
****h
D100
When D100 is designated as the first data register
“0”
(30h)
“1”
(31h)
1st
character
“2”
(32h)
“3”
(33h)
Incoming Data
****h
D100+n
****h
D101
The incoming data is divided, converted, and stored to data registers according to the receive format.
****h
D100
RXD Instruction 1
STX
(02h)
“1”
(31h)
“2”
(32h)
“3”
(33h)
Incoming Data
****h
D100+n
****h
D101
The incoming data is divided, converted, and stored to data registers according to the receive format.
Start delimiters are not stored to data registers.
ENQ
(05h)
“A”
(41h)
“B”
(42h)
“C”
(43h)
STX (02h)
When D100 is designated as the first data register
****h
D200
RXD Instruction 2
****h
D200+n
****h
D201
ENQ (05h)
When D200 is designated as the first data register
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