IDEC microsmart pentra, Руководство по программированию

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25: U
SER
C
OMMUNICATION
I
NSTRUCTIONS
25-10 FT1A S
MART
A
XIS
U
SER
’
S
M
ANUAL
FT9Y-B1382
Repeat Cycles
When a data register is designated to repeat, the received data is divided and converted in the same way as specified, and the converted data is
stored to consecutive data registers as many as the repeat cycles.
Example: Received data of 6 bytes is divided into 2-digit blocks, converted in ASCII to Binary, and stored to data registers starting
at D20.
(1) Repeat cycles = 2
(2) Repeat cycles = 3
Delimiter
A delimiter for the data register in the receive format can be designated. 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 SmartAxis 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 RXD2 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 SmartAxis discards the incoming data and waits for the next
communication.
0012h
D20
Repeat 1
0034h D21
ASCII to Binary conversion
Repeat 2
“1”
(31h)
“2”
(32h)
2 digits
1st block
“3”
(33h)
“4”
(34h)
2 digits
2nd block
0012h
D20
Repeat 1
0034h D21
ASCII to Binary conversion
Repeat 2
“1”
(31h)
“2”
(32h)
2 digits
1st block
“3”
(33h)
“4”
(34h)
2 digits
2nd block
“5”
(35h)
“6”
(36h)
2 digits
3rd block
0056h
D22
Repeat 3
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.