To do the initial setup for each connected EVM, click the (Configuration) icon on the menu to the left. Figure 4-10 shows an example of the configuration tool, which may change based on the device connected.
Figure 4-10 Configuration Tool
From this page you can set the number of EVMs you are using, and then for each EVM you can indicate the physical hardware switch settings and configure your shunt and CURRENT_LSB. Below is a description of each option and field on this page:
Number of EVMs
This setting is used to tell the GUI how many EVMs are connected to the SCB.
Note, the SCB and GUI only support up to four EVMs at a time with the same device on each EVM.
Changing this here also changes the same setting in the Results Data tab.
Selected EVM
This setting indicates which EVM you are currently changing settings for.
This also selects the EVM that is connected to the Registers page.
Hardware Switch Settings
Set these settings to match the physical switch settings on the EVM.
Note, this setting must be set before changing any other settings on this page. The GUI will block the other settings until this is set.
Changing this here also changes the same setting in the Results Data tab.
Shunt Full-Scale Differential Range
This is a shortcut to the ADCRANGE (ZOOM) setting from the Registers page, placed here for convenience.
Both this setting and the ADCRANGE setting from the Registers page change together.
Shunt/Current Configuration
This section is used to input shunt information as well as to help calculate the CURRENT_LSB and set the SHUNT_CAL register. Here is a description of how to use each field:
RSHUNT
Input the value of the used shunt resister in mΩ.
Max Expected Current
Input the value of the maximum expected current across the shunt resistor in Amps.
If the Max Expected Current field is left blank, then SHUNT_CAL can be adjusted manually, and the tool will tell you the True Max Current that can be measured with the EVM.
CURRENT_LSB
This is the calculated CURRENT_LSB value in Amps. This field gets populated automatically from the Max Expected Current field.
This field can be changed manually if desired, and changes will filter downward.
SHUNT_CAL
Calculated value for SHUNT_CAL based off of RSHUNT and CURRENT_LSB. When this field changes, the value is automatically written to the SHUNT_CAL register.
When CURRENT_LSB is specified, changing ADCRANGE will adjust this value automatically per data sheet equations.
This will happen if ADCRANGE is changed from either the configuration page or the register map.
If CURRENT_LSB is not specified, this value will remain unchanged, but the fields below will adjust to the new ADCRANGE.
This field can be changed manually if desired, and changes will filter downward.
Changing this value from the Registers page also changes it here.
True CURRENT_LSB
This is the actual CURRENT_LSB value in Amps back calculated from the SHUNT_CAL register with the given shunt resistor value.
This is the value used for calculations in the Results Data section.
True Max Current
This is the maximum measurable current in Amps based off of the VSHUNT and CURRENT registers, using RSHUNT and the True CURRENT_LSB for calculations.
Required Sensing Range
This shows the required sensing range to measure the Max Expected Current with the specified shunt resistor.
If a Max Expected Current is not specified, then the True Max Current field will be used instead.