N4DAC02 2-channel RS485
DAC module
Features:
1: Operating Voltage : DC 12 (DC 12-25V),
recommended power supply with small ripple
2: Operating Current : 12-13MA
3: MODBUS
RTU Command support 03 06 function code
4: CH1(O1)
output voltage is 0-5V, maximum output current is 20MA. 1-5V accuracy 1%,
<1V there is a ripple of 50HZ/40MV.
CH2(O2) output
voltage is 0-10V, maximum output current is 20MA. 2-10V accuracy 1%, <2V
there is a ripple of 50HZ/80MV.
5: The voltage resolution is 0.01V, the
output accuracy is 1%; if the error is greater than 1%, it can be calibrated
6 :MODBUS commands can be made serial
HyperTerminal (serial assistant) OR PLC Enter;
7 :Under the MODBUS command mode, it can
support up to 247 devices in parallel
8 :Size: 45 * 35 * 15mm
9 :Weight: 10g
Slave ID: Different "Sliver ID" can be
set by command, the maximum number is 247
Under the MODBUS command mode,the
slave ID must be correct
Modbus RTU Command Please refer to : "N4DAC02 modbus rtu protocol "
Note:
This is a low-cost digital-to-analog
conversion module based on the PWM+ADC solution. It has the following
disadvantages:
1 channel 1 (O1) has 1% accuracy at 1-5V,
<1V has 50HZ/40MV ripple, channel 2 (O2) has 1% accuracy at 2-10V, and
<2V has 50HZ/80MV Ripple.
2 channel 1 (O1) minimum output voltage is
0.05V, channel 2 (O2) minimum output voltage is 0.1V
3 There is a 10-20MS high pulse at the moment
of power-on
Wiring diagram:
Command Description, Please
refer to " N4AIA04 modbus rtu protocol "
N4DAC02 modbus
rtu protocol
Function code
|
RS485 address (Station address) (1) |
Function (1) |
Register address (2) |
Read number (2) |
CRC16 (2) |
|
|
03 Read |
|
|
|
|
|
06 Write |
|
|
|
|
Read-only register,Read Function code Is
03 |
||||
|
Register address |
Register contents |
Number of bytes |
Units |
Remarks |
|
0x0000 |
(CH1)O1 Voltage value |
2 |
0.01V |
such as: Input 0x00C8 Decimal 200 Output= 200 * 0.01 = 2.00V |
|
0x0001 |
(CH2)O2 Voltage value |
|||
|
Read / write register;
Read function code is 03 ,Write function code is 06 |
||||
|
0x0007 |
(CH1)O1 Voltage ratio |
2 |
0.1% millesimal |
This value can be
corrected when the Actual output voltage is greater than 1%, such as: 1000 means 1:1 1010: 1% increase 990: 1% decrease |
|
0x0008 |
(CH2)O2 Voltage ratio |
|||
|
0x000E |
RS485 address (Station address) |
2 |
|
Read Address 0XFF Write Address 1-247 |
|
0x000F |
Baud rate |
2 |
|
0~4 0:1200 1:2400 2:4800 3:9600（default） 4:19200 5: Factory reset |
Serial baud rate：9600（default），N，8，1
Modbus RTU Communication protocol：
Read the output voltage
value of channel 1/2, the unit is 0.01V
1.
Read Voltage value
Send data
|
RS485
address (Station
address) (1) |
Function
(1) |
Register
address (2) |
Read
number (2) |
CRC16(2) |
Returns
data
|
RS485
address (Station
address) (1) |
Function
(1) |
Number of bytes (1) |
data (n) |
CRC16(2) |
RS485 address(Slave ID) : 0x01~0xFE
Function
code 0x03
Register address：0x0000-0x0001,
Indicates 1-2channel value
Read number：0x0001-0x0002
For
example:
Send data(RS485 address is 1)：01 03 00
00 00 01 84 0A ;00 means channel 1
Returns
data：01 03 02 00 C8 B9 D2
01 RS485 address,03 Function,02 length,B9
D2 crc16
00C8 is
the Output voltage value, it is converted to decimal = 200, 200/100=2.00V；
For
example:
Send data(RS485 address is 1)：01 03 00
01 00 01 D5 CA ;01 means channel 2
Returns
data：01 03 02 01 F4 B8 53
01 RS485 address,03 Function,02 length, B8
53 crc16
01F4 is
the Output voltage value, it is converted to decimal = 500, 500/100=5.00V；
2.
Set Output
Voltage value
Set the
output voltage value of channel 1/2, the unit is 0.01VSend data
|
RS485
address (Station
address) (1) |
Function
(1) |
Register
address (2) |
Setting
Content (2) |
CRC16(2) |
Returns
data
|
RS485
address (Station
address) (1) |
Function
(1) |
Register
address (2) |
Register
value (2) |
CRC16(2) |
RS485 address(Slave ID) : 0x01~0xFE
Function code 0x06
Register address：0x0000-0x0001;
Indicates 1-2 channel value
Setting value: 2 bytes, unit 0.01V. The
voltage range set for channel 1 is 0.05-5V, and the voltage range set for
channel 2 is 0.10-10V.
For example 1: Let CH1
output 3.3V voltage. Input value 330 and convert it to hexadecimal 014A
Send frame: 01 06 00 00 01 4A 09 AD
Return frame: 01 06 00 00 01 4A 09 AD
For example 2: Let CH2
output 4V voltage. Input value 400 and convert it to hexadecimal 0190
Send frame: 01 06 00 00 01 90 88 36
Return frame: 01 06 00 00 01 90 88 36
3.
Read
Voltage ratio:
Send data
|
RS485
address (Station
address) (1) |
Function
(1) |
Register
address (2) |
Read
number (2) |
CRC16(2) |
Returns
data
|
RS485
address (Station
address) (1) |
Function
(1) |
Number of bytes (1) |
data (n) |
CRC16(2) |
RS485 address(Slave ID) : 0x01~0xFE
Function
code 0x03
Register address：0x0007-0x0008
; Indicates 1-2 channel value
Read number：0x0001-0x0002
Return
data: 0.1% millesimal
The voltage ratio can be corrected by this value
when the voltage reading deviation is greater than 1%. The default value is
1000 (3E8).
For example 1:
send data(RS485 address is 1)：01 03 00
07 00 01 35 CB; 07 is Channel 1
Returns
data：01 03 02 03 E8 B8 FA
03E8 is the
voltage ratio, which is 1000 in decimal and divided by 1000=1; indicating that
channel 1 does not need to modify the voltage value.
For example 2:
send data(RS485 address is 1)：01 03 00
08 00 01 05 C8; 08 is Channel 2
Returns
data：01 03 02 03 DE 38 EC
03DE is
the voltage ratio, which is 990 in decimal and divided by 1000=0.99; Indicates
that channel 2 reads 0.99 times the actual acquisition value.
4.
Set current
ratio
When the
actual output voltage deviation is greater than 1%, it can be corrected by this
value, the default is 1000 (03E8)
Send data
|
RS485
address (Station
address) (1) |
Function
(1) |
Register
address (2) |
Setting
Content (2) |
CRC16(2) |
Returns
data
|
RS485
address (Station
address) (1) |
Function
(1) |
Register
address (2) |
Register
value (2) |
CRC16(2) |
RS485 address(Slave ID) : 0x01~0xFE
Function
code 0x06
Register address：0x0007-0x0008
; Indicates 1-2 channel value
Setting Content：2Bytes
Setting value: 2 bytes, unit 0.1%. When this value
is set to 1000 (3E8), the voltage value does not change.
For example 1: Set the
channel 1 to 5V, but the actual output voltage is 4.9V. Output deviation:
5/4.9=1.020. Input 1020 (0X03FC) to correct the output error
Send frame: 01 06 00 07 03 FC 38 BA
Return frame: 01 06 00 07 03 FC 38 BA
For example 2: Set the
channel 2 to 4V, but the actual output voltage is 4.1V. Output deviation: 4/4.1=0.975.
Input 975 (0X03CF) to correct the output error
Send frame: 01 06 00 08 03 CF 48 AC
Return frame: 01 06 00 08 03 CF 48 AC
5.
Read RS485
address
Send data
|
RS485
address (Broadcast
address) (1) |
Function
(1) |
Register
address (2) |
Read
number (2) |
CRC16(2) |
Returns
data
|
RS485
address (
Broadcast address ) (1) |
Function
(1) |
Number of bytes (1) |
data (n) |
CRC16(2) |
Broadcast address 0xff
Function
code 0x03
Register address：0x000E
Read number：0x0001
For
example:
send data：FF 03 00
0E 00 01 F0 17
Returns
data：FF 03 02 00 01 50 50
FF Broadcast address，03 Function，02 length，01 is the
current module RS485 address , 50 50 crc16
Note:
When using this command, only one temperature module can be connected to the
RS485 bus, more than one will be wrong!
6.
Write
RS485 address
Send data
|
RS485
address (Station
address) (1) |
Function
(1) |
Register
address (2) |
Setting
Content (2) |
CRC16(2) |
Returns
data
|
RS485
address (Station
address) (1) |
Function
(1) |
Register
address (2) |
Register
value (2) |
CRC16(2) |
RS485 address(Slave ID) : 0x01~0xFE
Function
code 0x06
Register address：0x000E
Setting Content：2Bytes(1-247)
For
example, The current
RS485 address is 1, We need to change the RS485 address to 3:
send data(RS485 address is 1)：01 06 00
0E 00 03 A8 08
Returns
data：01 06 00 0E 00 03 A8 08
7.
Read baud rate
Send data
|
RS485
address (Station
address) (1) |
Function
(1) |
Register
address (2) |
Read
number (2) |
CRC16(2) |
Returns
data
|
RS485
address (Station
address) (1) |
Function
(1) |
Number of bytes (1) |
data (n) |
CRC16(2) |
RS485 address(Slave ID) : 0x01~0xFE
Function
code 0x03
Register address：0x000F
Read number：0x0001
For
example:
send data(RS485 address is 1)：01 03 00
03 00 01 74 0A
Returns
data：01 03 02 00 03 F8 45
01 RS485 address，03 Function，02 length，F8 45
crc16
03 means
the current baud rate is 9600bps
Baud rate corresponds to the number: 0: 1200 1: 2400 2: 4800 3: 9600 4: 19200
8.
Write baud rate
Send data
|
RS485
address (Station
address) (1) |
Function
(1) |
Register
address (2) |
Setting
Content (2) |
CRC16(2) |
Returns
data
|
RS485
address (Station
address) (1) |
Function
(1) |
Register
address (2) |
Register
value (2) |
CRC16(2) |
RS485 address(Slave ID) : 0x01~0xFE
Function
code 0x06
Register address：0x000F
Setting Content：2Bytes(0-4)
For
example, Change the baud rate to 4800bps:
send data(RS485 address is 1)：01 06 00
0F 00 02 38 08
Returns
data：01 06 00 0F 00 02 38 08
Baud rate corresponds to the number: 0: 1200 1: 2400 2: 4800
3: 9600 4: 19200
5: Factory reset
Note: 1 The baud rate will be updated when the
module is powered up again!
2 The
factory setting can be restored when the baud rate corresponding to the number
is 5. For example: 01 06 00 0F 00 05 79 CA
MODBUS
commands you can use "Modbus Poll" input, as shown below
（CRC check
generated automatically）
You can also use HyperTerminal serial input, as
shown below
（Manually
add CRC check）
