DA 12-4 (98), DA 12-2 (98) (CONTEC)

12-bit D / A conversion board for C bus.DA12-4 (98) has 4 channels, DA12-2 (98) has 2 channels.

Output: -10 to +10 V, Max 3 mA (bipolar only)
Error: + -1LSB (ambient temperature 25 degrees), 0.1% error at ambient temperature 0, 50 degrees
Element used: AD7545 equivalent
Conversion time: 600 ns after instruction execution
Number of occupied ports: 8 bits 2 ports
Power supply: DC + 5 V, Max 550 mA
Operating conditions: 0 to 50 degrees, 20 to 90% (without condensation)

Right side of the board when the card edge connector is on the right side and the card plastic is on the left side
The upper corner jumper always shorts the top two.
Port address setting by 8 series dip switches (SW1, SW2)
・ In the case of BASIC program
All eight SW1s are set to OFF (00), set the port address (00 to FF) by SW2: Port you want to set
Turn on the bit switch corresponding to the address.The 0th bit is invalid (it can be either ON or OFF).
・ In case of machine language program
Turn on the bit switch corresponding to the port address you want to set for both SW1 and SW2.0th bit
Is invalid (ON or OFF is acceptable).
(Example) F0D0H
SW1: ON-ON-ON-ON-OFF-OFF-OFF-OFF-OFF
SW2: ON-ON-OFF-ON-OFF-OFF-OFF-OFF-OFF
As a general rule, use lower-order two-digit port numbers D0 to DF.
Input / output in machine language program is limited to register indirect input / output instruction by DX register.

・ Port and data output format
Output to the D / A converter is performed through the 2-byte output port.Port address and data
The correspondence with each bit is as follows:

                          D7 D6 D5 D4 D3 D2 D1 D0
            　              　　Output data Output channel
Set port address + 0: 2 ^ 3 2 ^ 2 2 ^ 1 2 ^ 0 ※ ※ 2 ^ 1 2 ^ 0
Set port address +1: 2 ^ 11 2 ^ 10 2 ^ 9 2 ^ 8 2 ^ 7 2 ^ 6 2 ^ 5 2 ^ 4

"Set port address + 0"-> "Set port" when performing OUT instruction in byte unit
Execute in the order of "address + 1".

・ Relationship between output data and output voltage

  Output data Output voltage
2 ^ 11 --------2 ^ 0
0111 1111 1111 10V * 2047/2048 = + 9.99521V
0000 0000 0001 10 V * 1/2048 = + 4.88 mV
0000 0000 0000 0V
1111 1111 1111 -10 V * 1/2048 = -4.88 mV
1000 0000 0000 -10V * 2048/2048 = -10V

・ Output channel selection
The choice of output channel is determined by the data given to the D1 and D0 bits of the configured port address:

   D1 D0
   0 0 --------- CH0
   0 1 --------- CH1
   1 0 --------- CH2
   1 1 --------- CH3

・ 36-pin interface connector
The pin numbers are 1 for the upper right corner when viewed from the back of the board 1, 2 for the left, 18 for the upper left corner, 17 for the right, lower right corner
Is 19, its left 20, its lower left corner 36, its right 35.

Pin 11: OUT3 (CH3)
Pin 13: OUT2 (CH2)
Pin 15: OUT1 (CH1)
Pin 17: OUT0 (CH0)
Pin 29: Output signal common (analog ground)
Pin 31: Output signal common (analog ground)
Pin 33: Output signal common (analog ground)
Pin 35: Output signal common (analog ground)

・ Function of potentiometer on board
The rightmost potentiometer is VR1 when viewed from the back of the board, and the numbers increase as it goes to the left, and the leftmost is VR8.

VR1: CH3 offset adjustment
VR2: CH3 gain adjustment
VR3: CH2 offset adjustment
VR4: CH2 gain adjustment
VR5: CH1 offset adjustment
VR6: CH1 gain adjustment
VR7: CH0 offset adjustment
VR8: CH0 gain adjustment

Offset adjustment is adjustment of -10.000V, gain adjustment is adjustment of + 9.995V.