RTD Embedded Technologies, Inc.
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39
DM35425HR User’s Manual
0x81:
Channel Threshold
–
One of the channels has exceeded the High or Low threshold. Check the CH_THRESH_STAT
registers.
0x82:
Pre-Start Buffer Filled
0x83:
Start Trigger
0x84:
Stop Trigger
0x85:
Post-Stop Buffer Filled
0x86:
Sampling has completed and the FIFO is empty (all data transferred to host)
0x87:
Pacer
–
The pacer clock has ticked.
6.3.16
CH
N
_FRONT_END_CONFIG
(M
ASKABLE
R
EAD
/W
RITE
)
Refer to
on page 24 for more information about the front end circuit.
This provides up to 16 bits to configure the Front End for this ADC Channel, to allow adjustment of gains, ranges.
B[7:6]: CH_DELAY
o
CH_DELAY [1:0] = 00: No Channel to Channel Delay
o
CH_DELAY [1:0] = 01: Half Sample Clock Channel to Channel Delay
o
CH_DELAY [1:0] = 10: Full Sample Clock Channel to Channel Delay
o
CH_DELAY [1:0] = 11: 2 Full Sample Clock Channel to Channel Delay
B[5]: CH_ENABLE 0 = Channel Disabled
1 = Channel Enabled
B[4:2]: GAINSEL
o
GAINSEL [2:0] = 000: Gain of 1
o
GAINSEL [2:0] = 001: Gain of 2
o
GAINSEL [2:0] = 010: Gain of 4
o
GAINSEL [2:0] = 011: Gain of 8
o
GAINSEL [2:0] = 100: Gain of 0.5
B[1]: BIP_UNI
0 = Bipolar operation
1 = Unipolar operation
B[0]: SE_ DIFF
0 = Single-Ended Input
1 = Differential Input
Table 18: ADC Full-Scale Settings
GAINSEL[2:0] Signal Path Gain Unipolar Mode Bipolar Mode
100
0.5
n/a
±10V
000
1
0-10V
±5V
001
2
0-5V
±2.5V
010
4
0-2.5V
±1.25V
011
8
0-1.25V
±0.625V
NOTE: The Front End may take up to 800ns to settle after writing to this
register.
6.3.17
CH
N
_FIFO_DATA_CNT
(R
EAD
)
This register shows the current sample count that is available in the ADC channel FIFO.
6.3.18
CH
N
_FILTER
(R
EAD
/W
RITE
)
The programmable digital filter provides a single pole Infinite Impulse Response (IIR) filter on each channel. This a unity-gain filter. The filtered
data has a value of: