RB8509 -- 8-channel 12-bit ADC
Purpose
Measure a voltage.
Description
Module RB8509 is a 8-channel 12-bit analog to digital converter (ADC).
The module has eight analog inputs and a trigger input to start a data acquisition. A data acquisition can also be started by a software trigger.
Module RB8509 contains the following parts:
- a channel selector to select one of the eight inputs [ch0..ch7]
- a gain selector to select one of the four gains [1, 2, 4, 8]
- a 12-bit data Analog to Digital Converter
The following variations of this module are known to exist:
- 8-channel input, no external trigger input
- 4-channel input
Configuration
At production time, the ADC is configured for unipolar or bipolar operation and its input voltage range is defined as 10 or 20V.
The following table shows the volt-per-bit values for the various input voltage ranges.
Voltage range | volt-per-bit bipolar
----------------------+--------------------------
0 .. 10.2375 V | 2.5 mV 0
-5.12 .. 5.1175 V | 2.5 mV 1
-10.24 .. 10.235 V | 5 mV 1
Default configuration
rb8509_adc12 "name"
{
address = 0xC0,
bipolar = true,
volt_per_bit = 5e-3
}
When the Rulbus configuration file is read, ADCs are configured as follows:
- external trigger disabled
- gain 1 selected
- channel 0 selected
Modules | |
| RB8509 ADC12 Autoscale | |
| determine and set amplifier gain to fit current signal. | |
| RB8509 ADC12 Close | |
| close an ADC. | |
| RB8509 ADC12 Convert | |
| start an analog to digital conversion. | |
| RB8509 ADC12 Enable Ext Trigger | |
| enable or disable external trigger-input. | |
| RB8509 ADC12 Get Channel | |
| get currently selected channel [0..7]. | |
| RB8509 ADC12 Get Ext Trigger Level | |
| the current external trigger level. | |
| RB8509 ADC12 Get Gain | |
| get currently selected gain [1,2,4,8]. | |
| RB8509 ADC12 Get Value | |
| issue software trigger and return conversion value, may return 1 on timeout; OR wait for external trigger and return conversion value. | |
| RB8509 ADC12 Get Voltage | |
| issue software trigger and return input-voltage measured, may return 1 on timeout; OR wait for external trigger and return input-voltage measured. | |
| RB8509 ADC12 Get Voltperbit | |
| the ADC's input sensitivity configuration. | |
| RB8509 ADC12 Open | |
| open an ADC. | |
| RB8509 ADC12 Set Channel | |
| select channel [0..7]. | |
| RB8509 ADC12 Set Gain | |
| select gain [1,2,4,8]. | |
| RB8509 ADC12 TEST | |
| test the ADC VIs and physical ADC module. | |
| RB8509 ADC12 isBipolar | |
| true if ADC has bipolar configuration. | |
| RB8509 ADC12 isEnabled Ext Trigger | |
| true if external trigger-input is enabled. | |
| RB8509 ADC12 isReady | |
| true if result is available; flag is reset by reading result. | |