E850-DTU(4440-GPRS) datasheet
Copyright ©2012–2018
，成都亿佰特电子科技有限公司
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Switch quantity change uploading protocol is as follows, The frame headers 0xAA and 0xBB are
fixed, and the values of DI1, DI2, DI3, and DI4 are 0x00, 0x01, and 0xFF.
0x00 represents the switch quantity input disconnected
0x01 represents the switch quantity input closed
0xff represents the switch quantity input not changed
The values of DI1, DI2, DI3, and DI4 in the table indicate that the DI1 and DI2 states are updated
to be disconnected, the DI3 state is updated to be closed, and the DI4 state is not changed. The last
two bytes are Modbus CRC16 calculated values.
Header
DI1
DI2
DI3
DI4
Modbus CRC
0xAA 0xBB
0x00
0x00
0x01
0xff
0xBD 0xDA
4.3.3 Switch quantity output DO time setting
The switch quantity pulse output time setting is to set the switch output time (relay NO, COM
closing time), the corresponding Modbus register is 40083 (0x0052), its value range is 300-65535ms,
if the value is lower than 300ms, default switch output closed to the holding state, that is, the switch
output is holding as closed. If it is set to 300ms and above, such as 500ms, after the switch output
close command is sent, the switch quantity will be closed for 500ms, and then automatically
disconnected after 500ms.
4.3.4 Restart switch quantity output state setting
This is the setting of whether the device hodes the state when restarts after power off, or restartes
to maintain the specific output state. This function is valid only when the device switch output time
setting register value is less than 300ms.
The restart switch quantity output state setting corresponding to Modbus register is 40085
(0x0054), and its value range is 0x00-0x10. When the value of this register is 0x10, it is maintained to
the last switch output state after power-off and restart; when the value of this register is 0x00-0x0F,
the restart switch output state is decided by the lower four bits, bit4 corresponds to DO4, bit3
corresponds DO3, bit2 corresponds to DO2, bit1 corresponds to DO1. When power is on, DO4 and
DO2 are in the closed state (relay NO, COM is closed), DO3, DO1 are disconnected (relay NO, COM
is disconnected), the corresponding register value is 00001010, that is 0xa0, "1" is the closed state,
and "0" is the disconnected state.
