PCI-1718 Series User Manual 70
DA11 ~ DA0 Analog to digital data
DA0 The least significant bit (LSB) of the D/A data
DA11 The most significant bit (MSB)
When you write data to D/A channels, write the low byte first. The low
byte is temporarily held by a register in the D/A and not released to the
output. After you write the high byte, the low byte and high byte are
added and passed to the D/A converter. This double buffering process
protects the D/A data integrity through a single step update.
The PCi-1718 cards provide a precision fixed internal -5 V or -10 V refer-
ence, selectable by means of Jumper JP10. This reference voltage is
available at connector CN3 pin 11. If you use this voltage as the D/A ref-
erence input, the D/A output range is either 0 to +5 V or 0 to +10 V. You
can also use an external DC or AC source as the D/A reference input. In
this case, the maximum reference input voltage is ±10 V, and the maxi-
mum D/A output ranges are 0 to +10 V or 0 to -10 V.
Connector CN3 supports all D/A signal connections. Chapter 3 gives con-
nector pin assignments and a wiring diagram for D/A signal connections.
C.10 FIFO Interrupt Control — BASE+06H
FINT Enable/disable FIFO interrupt
0 FIFO interrupt disabled
1 FIFO interrupt enabled
Table C.12: Register for FIFO Interrupt Control
Write FIFO interrupt control
Bit # 7 6543210
BASE + 06H AD12_16 X X X X X X FINT