Output Enable Bit; Module Resolution - Automation Direct DL405 User Manual

Output Enable Bit

Module Since the module has 12-bit resolution, the analog signal is made of 4096 counts
Resolution ranging from 0–4095. For output formats of –2047 to +2047, we still have 4095
counts. For example, with a 0 –10V scale and 0 to 4095 output format, you would
send a 0 to get a 0V signal, and 4095 to get a 10V signal. This is equivalent to a
binary value of 0000 0000 0000 to 1111 1111 1111, or 000 to FFF hexadecimal. The
following diagram shows how this relates to each signal range.
Each count can also be expressed in
terms of the signal level by using the
equation shown. The following table
shows the smallest change in signal
level due to a value change of 1 LSB
count.
The next to most significant bit (bit 14) is
the Output Enable bit. Turning it on
enables all four channels. Turning it off
causes all output signal levels to go to
zero volts, and clears the module's
internal data registers for all channels.
After an off-to-on transition of the Output
Enable bit, each output stays at zero
volts until the channel select bits select
the channel and the CPU writes a
non-zero value to it.
Output Range Signal Span
0–5V
0–10V
$5V
$10V
F4–04DA–2 Analog Voltage Output
MSB
1 1 1
5 4 3
Resolution + H * L
H = high limit of the signal range
L = low limit of the signal range
Divide By
(H – L)
5V 4095
10V 4095
10V 4095
20V 4095
V40501
LSB
1 1 1 9 8 7 6 5 4 3 2 1
2 1 0
– output enable bit
4095
Smallest Change
1.22 mV
2.44 mV
2.44 mV
4.88 mV
14–13
0