PIO-821 Series Card
45 kS/s 12-bit, 16-ch A/D, 1-ch D/A Multi-function DAQ Board
User Manual, Ver. 2.0, Mar. 2015, PMH-019-20, Page: 52
7.3.9 D/A Buffer Register
(Write): wBase+0xd0
D/A Low Byte Data Format
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
D7
D6
D5
D4
D3
D2
D1
D0
(Write): wBase+0xd4
D/A High Byte Data Format
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0
0
0
0
D11
D10
D9
D8
The D/A converter will convert the 12 bits digital data to analog output. The low 8 bits of D/A
channel are stored in address wBase +4 and high 4 bits are stored in address wBase +5. The D/A
output latch registers are designed as a “double buffered” structure, so the analog output latch
registers will be updated until the high 4 bits digital data are written. The user must send low 8 bits
first and then send high 4 bits to update the 12 bits AD output latch register.
7.3.10 D/I Input Buffer Register
Read): wBase+0xd8
D/I Low Byte Data Format
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
D7
D6
D5
D4
D3
D2
D1
D0
(Read): wBase+0xdc
D/I High Byte Data Format
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
D15
D14
D13
D12
D11
D10
D9
D8
DI 16 bits input data:
D15 to D0, D15=MSB, D0=LSB
The PIO-821 series card provides 16 TTL compatible digital inputs. The low 8 bits are stored in
address wBase +0xd8. The high 8 bits are stored in address wBase +0xdc.
