157
Setup Area Allocations
Section 5-2
Clearing/Holding the
Contents of the
Reception Buffer in
Full-duplex Mode (Unit
Ver. 1.2 or Later Only)
Set to either clear (OFF) or hold (ON) the contents of the reception buffer
when the protocol macro starts.
OFF: Clear
When set to clear (OFF), the contents of the reception buffer will be cleared
when the protocol macro is executed.
ON: Hold
When set to hold (ON), the contents of the reception buffer will not be lost if
data acquisition fails after execution of the protocol macro.
This function prevents loss of data during full-duplex communications.
Data Conversion Timing
for Link Word
Specifications (Unit Ver.
1.2 or Later Only)
Set to perform I/O refresh upon request or continuously, as follows:
OFF: On-request I/O refresh (Immediate refresh mode)
Data exchange is performed during I/O refresh when a refresh request is sent
to the CPU Unit for each send/receive command that is executed. A time
delay will occur after the send command is executed until the actual message
is sent when this method is used.
ON: Continuous I/O refresh (Cyclic refresh mode)
During protocol macro execution, I/O refreshing is continuously performed
with the CPU Unit, the data in the link word area is refreshed from the CPU
Unit, and the data in the Board/Unit is accessed during SEND/RECEIVE com-
mand execution. When the send command is executed with this method, the
actual message can be sent immediately.
Maximum Number of
Send/Receive Data Bytes
From 200 bytes up to a maximum of 1,000 bytes can be set in hexadecimal,
i.e., between 00C8 Hex and 03E8 Hex. Any setting below 00C8 Hex, will be
treated as 00C8 Hex; any setting above 03E8 Hex, will be treated as 03E8
Hex.
Note
Flow Control and Maximum Number of Send/Receive Data Bytes
There is a 2.5-Kbyte reception buffer for each serial port in a Serial Communi-
cations Board or Unit. When using flow control, initiate flow control after
receiving about 2 Kbytes, and then release control after processing all but
0.5 Kbytes of receive data. Up to 1,000 bytes (500 words) of data can be
stored for each RECV command if 2 Kbytes of receive data is first stored in
the buffer and 1,000 bytes (03E8 Hex) is set as the maximum number of send/
receive data bytes.
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...