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177
Using Protocol Macros
Section 5-4
The number of send words in S+1 and the following words is stored in the
rightmost 8 bits of S. The setting range is 01 to FA Hex (250 words or less). S
is also included in the number of words. The data to be sent is stored in S+1
and the following words.
Note
When there is no send data, set S to #0000.
First Receive Data Storage
Word (R)
R specifies the first word of the area used to initialize the reception buffer or
the first word of the area used to store the receive data.
Before Execution of PMCR(260)
The contents of R+1 and following words are set in the reception buffer. The
number of words of data from R through the end of the receive data is speci-
fied in the rightmost 8 bits of R. The range that can be set is 02 to FA Hex (2 to
250 words). If 00 Hex or 01 Hex is set, the reception buffer will remain cleared
after PMCR(260) execution and before executing the communications
sequence.
After Execution of PMCR(260)
The number of words of receive data in R+1 and the following words is stored
in the rightmost 8 bits of R. The range is 01 to FA Hex (250 words or less). R
is also included in the number of words. The receive data is stored in R+1 and
the following words. For details, refer to
Receive Data Storage Area Function
Note
1.
The function of the receive data storage words (start from R for the number
of words specified in R) differs before and after execution of PMCR(260).
a) Before Execution of PMCR(260)
The contents of the receive data storage words is used as initialization
data for the reception buffer before the communications sequence is
executed.
b) After Execution of PMCR(260)
Data received for the RECV command is stored in the receive data
storage words if there is response data to be written.
2.
When there is no receive data, set R to #0000.
PMCR(260) Operation
When PMCR(260) is executed, the communications sequence specified in C2
is executed for the communications port specified in bits 12 to 15 of C1 (inter-
nal logical port 0 to 7) from the serial port specified in bits 08 to 11 (physical
port) of C1 of the device with the unit address specified in bits 00 to 07 of C1.
If an operand is specified as a variable in the send message, data starting in
S+1 for the number of words specified in S is used as the send data. If an
operand is specified as a variable in the receive message, data will be
received in words starting from R+1 and the number of words of received data
will be automatically stored in R.
If reception processing fails, the data that was stored started at R+1 (i.e., the
number of words specified in R) is again read from the reception buffer and
stored again beginning at R+1. This ensures that the current data will not be
cleared and that the previous receive data will be maintained when receptions
fail.
Number of receive words
Receive data
Number of words including R
Word
R
R+1
R+n
0
0
15
12 11
08 07
00
Summary of Contents for SYSMAC CJ1W-SCU21-V1
Page 3: ...iv...
Page 5: ...vi...
Page 9: ...x...
Page 15: ...xvi...
Page 89: ...60 Basic Operating Procedure Section 1 9...
Page 151: ...122 RS 232C and RS 422A 485 Wiring Section 3 4...
Page 173: ...144 Host Link Function for Replacing Existing PLCs Section 4 6...
Page 223: ...194 Enhanced Protocol Macro Functions Section 5 6...
Page 277: ...248 Communications Frames Section 6 8...
Page 291: ...262 Basic Operating Procedure in No protocol Mode Section 7 4...
Page 301: ...272 Auxiliary Area and CIO Area Allocations Section 8 3...
Page 391: ...362 Introduction Appendix A...
Page 421: ...392 CompoWay F Master Protocol Appendix B...
Page 513: ...484 E5 K Digital Controller Read Protocol Appendix F...
Page 571: ...542 E5ZE Temperature Controller Write Protocol Appendix I...
Page 587: ...558 E5 J Temperature Controller Protocol Appendix J...
Page 627: ...598 ES100 Digital Controller Protocol Appendix K...
Page 661: ...632 V500 V520 Bar Code Reader Protocol Appendix M...
Page 697: ...668 3Z4L Laser Micrometer Protocol Appendix N...
Page 717: ...688 Visual Inspection System Protocol Appendix O...
Page 755: ...726 V600 V620 ID Controller Protocol Appendix P...
Page 763: ...734 Hayes Modem AT Command Protocol Appendix Q...
Page 767: ...738 Changing Communications Port Settings Using STUP 237 Appendix R...
Page 781: ...752 Revision History...