4
Allegro MicroSystems
955 Perimeter Road
Manchester, NH 03103-3353 U.S.A.
www.allegromicro.com
Once the part is powered on, values for “VCC [V]” and “ICC [mA]”
will populate with the measured values. Verify that the voltage is
what is desired and that the device is consuming approximately
10 mA (maximum of 12 mA).
To read the output of the ACS71240, select “Read Output” high-
lighted green in Figure 12. Verify the Output [V] is a reasonable
number, around 2.5 volts with zero external field applied if test-
ing a bidirectional part with 5 volts typical VCC (0.5 volts with
zero external field applied for a unidirectional device).
To turn the part off, select “Power Off” to the left of “Power On”,
highlighted in blue in Figure 14 above. Clicking “Power Off” will
cause ICC to fall to ≈ 0 mA.
Reading from and Writing to the Part
Note before reading and writing to the part, the part must be con-
nected and powered on using the programmer GUI.
It is recommended that the user save the memory to a tabular file
before experimenting with programming so the user can return
the device to its original factory programmed state if necessary.
See the Saving and Loading Memory Files section below.
To read a field, select the desired field by checking the box under
“Select” to the left of the register name and click the “Read
Selected” button highlighted in red in Figure 15.
To write to a field, select the desired field by checking the box
under “Select” to the left of the name. Change the value under
“Code” to the desired value and press Enter. Click “Write
Selected” button highlighted in blue in Figure 15.
To verify that field was written to the device, do the follow-
ing: click “Clear Selected” causing the values in the “Code”
and “Value” cells to disappear. Then click “Read Selected”. The
values that were written will reappear in the “Code” and “Value”
cells verifying the user correctly wrote to the part.
Figure 13: “Read Selected” and “Write Selected” buttons
Below, each option on the programmer menu has been briefly defined:
• Read Selected: reads value of the selected field.
• Write Selected: writes entered value to the part.
• Zero Selected: this option will zero the selected field but will
not write zero to the device unless “Write Selected” is clicked.
• Clear Selected: this option will hide and clear the value of the
selected field but will not change the value.
• Select All: selects all fields.
• Deselect All: deselects any and all selected fields.
Note that clicking on the name of a selected field will define the
field to the user. Hovering over a field with the PC cursor will tell
the user the address of that field (see Figure 13).
Figure 14: Hovering over a eld shows the address
Accessing the Register Diagram
To access the register diagram, hover over “Help” on the menu
bar. Select “ACS71240 Register Diagram”. This will open a dia-
log window identical to the window in Figure 18 below. See the
appendix section below for a larger register diagram.
Figure 15: ACS71240 Register Diagram
Manchester Programming Protocol
Under “Setup” “Device Setup…”, the dialog menu in Figure 16
below will appear. In this menu, the user can change various char-
acteristics of the Manchester programming protocol used by the
ASEK-20. To restore these settings to their default settings, click
“Restore Defaults” as highlighted in red in Figure 16.
