Mitsubishi Electric FX3U-232-BD User Manual page 24

FX Series PLC User's Manual - Data Communication Edition
5. Creating Programs
5.1 Outline of Communication between FX PLC and 232IF ........................................................... G-14
5.1.1 For FROM and TO instructions ................................................................................................. G-14
5.1.2 For direct specification of buffer memory (U\G) .................................................................. G-14
5.2 FROM and TO Instructions ....................................................................................................... G-15
5.2.1 FROM instruction....................................................................................................................... G-15
5.2.2 TO instruction ............................................................................................................................ G-16
5.3 Direct Specification of Buffer Memory (U\G)....................................................................... G-17
5.4 Buffer Memory (BFM)................................................................................................................ G-18
5.4.1 Buffer memory list...................................................................................................................... G-18
5.4.2 Communication format <BFM #0>............................................................................................. G-20
5.4.3 Command <BFM #1> ................................................................................................................ G-24
5.4.4 Maximum number of receivable bytes <BFM #2> ..................................................................... G-25
5.4.5 Receiving timeout time <BFM #3> ............................................................................................ G-25
5.4.6 Sending header <BFM #5 (highest-order 2 bytes) and BFM #4 (lowest-order 2 bytes)>.......... G-25
5.4.7 Sending terminator <BFM #7 (highest-order 2 bytes) and BFM #6 (lowest-order 2 bytes)>..... G-25
5.4.8 Receiving header <BFM #9 (highest-order 2 bytes) and BFM #8 (lowest-order 2 bytes)> ....... G-25
5.4.9 Receiving terminator <BFM #11 (highest-order 2 bytes) and BFM #10 (lowest-order 2 bytes)>... G-26
5.4.10 Receiving suspension waiting time <BFM #12>...................................................................... G-26
5.4.11 Amount of remaining send data <BFM #13>........................................................................... G-26
5.4.12 Amount of received data buffers <BFM #14>.......................................................................... G-26
5.4.13 Sending sum result <BFM #15> .............................................................................................. G-27
5.4.14 Receiving sum result <BFM #16> ........................................................................................... G-27
5.4.15 Time from CS ON to sending start <BFM #20>....................................................................... G-27
5.4.16 Time from actual sending completion to RS OFF <BFM #21>................................................ G-27
5.4.17 Status <BFM #28>................................................................................................................... G-28
5.4.18 Error code <BFM #29> ............................................................................................................ G-29
5.4.19 Model code <BFM #30> .......................................................................................................... G-29
5.4.20 Number of bytes to be sent <BFM #1000>.............................................................................. G-29
5.4.21 Send data buffer <BFM #1001 to 1256> ................................................................................. G-29
5.4.22 Number of received bytes <BFM #2000>................................................................................ G-29
5.4.23 Receive data buffer <BFM #2001 to 2256>............................................................................. G-29
5.4.24 Preliminary receive data buffer for interlink connection mode <BFM #2257 to 2271> ............ G-29
5.5 Operation of Control Line .......................................................................................................... G-30
5.5.1 When control line is not provided [BFM #0, (b9, b8) = (0, 0)].................................................... G-30
5.5.2 When control line is in standard RS-232C mode [BFM #0, (b9, b8) = (0, 1)] ............................ G-31
5.5.3 When control line is in RS-232C interlink mode [BFM #0, (b9, b8) = (1, 1)].............................. G-32
6. Practical Program Examples
6.1 Example of Sending/Receiving 16-Bit Buffer Length Data........................................................ G-33
6.2 Sending/Receiving 8-Bit Buffer Length Data............................................................................. G-37
7. Troubleshooting
7.1 Check Items .............................................................................................................................. G-41
7.2 Error Codes............................................................................................................................... G-41
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Table of Contents
G-14
G-33
G-41