Specifications

7. Application Instructions
© DELTA ELECTRONICS, INC. ALL RIGHTS RESERVED
7-42
D104 lower 00 H
D105 lower 12 H
Data content
D106 lower 02 H CRC CHK Low
D107 lower 07 H CRC CHK High
PLC receives data register (response messages of VFD-B)
Registers DATA
D120 lower 01 H Address
D121 lower 06 H Function
D122 lower 20 H
D123 lower 00 H
Data address
D124 lower 00 H
D125 lower 12 H
Data content
D126 lower 02 H CRC CHK Low
D127 lower 07 H CRC CHK High
 Footnote:
Ϩʳ RS-485 communication RS / MODRD / MODWR / FWD / REV / STOP
/ RDST / RSTEF / MODRW commands relation flag signal:
Flag Function Explanation
M1120
It is used to set communication latch. PLC will reset
communication protocol setting according to special data
register D1120 after the first program scan. When second
program scan starts and RS command is executed, it will
reset communication protocol setting according to special
data register D1120. If communication protocol is fixed,
M1120 can be set to ON. At this time, communication protocol
setting won’ t be reset as RS / MODRD / MODWR / FWD /
REV / STOP / RDST / RSTEF / MODRW is executed even if
D1120 setting is changed.
M1121 It indicates that PLC can transmit data now.
M1122
Transmit request. Users need to set M1122 to ON by pulse
command when using RS / MODRD / MODWR / FWD / REV /
STOP / RDST / RSTEF / MODRW command to transmit and
receive data. If the command above is executing, PLC will
transmit and receive data. M1122 will be clear after the
commands above finish transmitting.
Flag Function Explanation
M1123
Receive completely. M1123 will be set to ON after RS /
MODRD / MODWR / FWD / REV / STOP / RDST / RSTEF /
MODRW
commands finish executing. User can deal with
received data when M1123 is set to ON and clear M1123 to
OFF when finish handling them.
M1124
Wait for receiv
ing. When M1124 is set to ON, it means PLC is
waiting for receiving data.
M1125
Received function disable. When M1125 is set to ON, the
state of PLC transmits function disable.
M1126
Please refer to following chart for selecting user/system
definition and STX/ETX.
M1127
M1127 should be clear to OFF when MODRD / RDST /
MODRW commands finish receiving at ASCII mode.
M1128 transmitting / receiving indication
M1129
Receive time out. This flag will be active, if D1129 is set and
receive data doesn’ t finish within the setting time. If the state
disable, M1129 should be clear to OFF.
M1130
Please refer to following chart for selecting users/system
definition and STX/ETX.
M1131
M1131=ON during MODRD / RDST / MODRW convert to
HEX. Otherwise M1131 will be OFF.
M1140 MODRD / MODWR / MODRW data receive error
M1141 MODRD / MODWR / MODRW command parameter error
M1142 Data receive error of VFD-A convenience command
M1143
ASCII / RTU mode selection, ON is RTU mode and OFF is
ASCII mode.
M1161
8/16 bits handle mode selection. ON is 8 bits mode and OFF
is 16 bits mode.
Ϩʳ Special register of RS-485 communication RS / MODRD / MODWR /
FWD / REV / STOP / RDST / RSTEF / MODRW command relative
setting