USING A1330 ASEK DLLS TO MAKE TWO-POINT LABVIEW

APPLICATION INFORMATION

296186-AN

MCO-0000910

USING A1330 ASEK DLLS TO MAKE

TWO-POINT LABVIEW PROGRAMMER

INTRODUCTION

The Allegro A1330 is a 360° angle sensor IC that pro-

vides contactless high-resolution angular position based

on circular vertical Hall (CVH) technology. The A1330

incorporates programmable angle scaling, angle offset,

and several other registers in EEPROM to enable a full

signal output to be achieved for applications requiring

less than 360° rotation, such as throttle position, accel-

eration/brake pedal position, and other short-stroke

applications. For details on how to use the A1330 in these

applications, refer to the A1330 datasheet and related

application notes posted on the Allegro website (https://

www.allegromicro.com/en/insights-and-innovations)

and download the Allegro A1330 Sample Programmer

Graphical User Interface (GUI) at https://registration.

allegromicro.com/#/.

The A1330 Sample Programmer GUI is written in the C#

language, but when customers enter mass production

(MP) phase, they commonly use LabVIEW to implement

MP software. This application note provides guidelines

on how to use the A1330 dynamically linked library (DLL)

with LabVIEW.

Hardware and software used in this application note

include:

• ASEK-20/21

• ASEK-1330-SUBKIT-T

• Operating System: Windows 10 64-bit

• LabVIEW: 2017 64-bit

• A1330 DLL: V2.4.6

Figure 1, Figure 2, and Figure 3 show typical transfer

function curves of three different applications. These

three curves will be implemented in this application note

using the A1330 DLL with LabVIEW.

By James Zhao

Allegro MicroSystems

Figure 1. Single Die Throttle Application Curve

Figure 2. Dual Die Throttle Application Curve

955 PERIMETER ROAD • MANCHESTER, NH 03103 • USA

+1-603-626-2300 • FAX: +1-603-641-5336 • ALLEGROMICRO.COM

APPLICATION INFORMATION

296186-AN

MCO-0000910

Figure 3. Dual Die Pedal Application Curve

For the above transfer functions in Figure 1, Figure 2, and Figure 3, note that if the desired low level is less than

0.35 V or the desired high level is higher than 4.65 V, some devices may not be able to reach this value because

of DAC output limitations; see datasheet specification for guaranteed minimum DAC output. Also, if the desired

offset multiplied by the desired gain is greater than 180°, insufficient adjustment exists in the A1330 to meet this

requirement. As an example, if the desired gain is 4×, the offset cannot be larger than 45 mechanical degrees.

Characteristics Symbol Test Conditions Min. Typ. Max. Units

Output Saturation Voltage

OUT(MAX)

Max input angle position; V

= 5 V,

HIGH_CLAMP = 0

4.65 4.75 – V

OUT(MIN)

0° input angle position; V

= 5 V,

HIGH_CLAMP = 0

– 0.25 0.35 V

USING A1330 ASEK DLLS IN LABVIEW FOR TWO-POINT PROGRAMMING

Basic Steps

Download and extract the Allegro A1330 libraries from https://registration.allegromicro.com/#/. The following files

will be found in the library directory:

The ASEK20_A1330.dll is the DLL file needed for LabVIEW.

955 PERIMETER ROAD • MANCHESTER, NH 03103 • USA

+1-603-626-2300 • FAX: +1-603-641-5336 • ALLEGROMICRO.COM

APPLICATION INFORMATION

296186-AN

MCO-0000910

1. Open the LabVIEW window, click the ‘Connectivity’ section of ‘Functions’, then click the ‘.NET’ icon;

see Figure 4.

Figure 4

2. Drag the constructor node to the VI window. A “Select .NET Constructor” window will appear. Choose the

Assembly Menu as ‘ASEK20_A1330’, Objects Menu as ‘ASEK20_A1330’, Constructors Menu as ‘ASEK20_

A1330()’, and then click ‘OK’ button, as shown in Figure 5.

Figure 5

955 PERIMETER ROAD • MANCHESTER, NH 03103 • USA

+1-603-626-2300 • FAX: +1-603-641-5336 • ALLEGROMICRO.COM

APPLICATION INFORMATION

296186-AN

MCO-0000910

3. Now the constructor node should be ASEK20_A1330. In order to facilitate communication with the

ASEK-20, select the communication port the ASEK-20 will use by dragging an invoke node from the .NET

palette, wiring the reference from the constructor node to the reference on the invoke node, and choosing

the ‘SetCommunicationPort’ as Method, as shown in Figure 6. Create a string constant with the com port

name that the ASEK-20 is using and connect it to port; here, the PC port is ‘COM12’, as shown in Figure 7.

Figure 6

4. In order to communicate with the part, the communication protocol must be initialized; therefore, create an-

other invoke node, wire it in to the reference, and select the method “InitializeDeviceManchester”, as shown

in Figure 7.

Figure 7

5. Turn on the device and create an invoke node using the ‘SetVcc’ method. This function in C# script is shown

below:

SetVcc(double supplyVoltage, uint unlockAddress, uint unlockCode);

Set supplyVoltage to 5.026 to make the supply from ASEK-20/21 output 5 V. The A1330 must also have the

customer code supplied during power-up to unlock the registers for reading and writing. The unlockAddress

is 0x1F and unlockCode is 0x4F50454E. Create hexadecimal numeric constants with ‘0x1F’ and

‘0x4F50454E’, and connect them to corresponding inputs, as shown in Figure 7.

955 PERIMETER ROAD • MANCHESTER, NH 03103 • USA

+1-603-626-2300 • FAX: +1-603-641-5336 • ALLEGROMICRO.COM

APPLICATION INFORMATION

296186-AN

MCO-0000910

Now that the device is powered up, it can be written to or read from. For verification purposes, the chip ID can be

read as shown in Figure 8. The ‘ReadMemory’ function in C# script is shown below:

ReadMemory(MemoryAccessType type, uint[] address, Progress readProgress);

Create an invoke node using the ‘ReadMemory’ method. There are four options that can be chosen for ‘type’:

‘primary’, ‘extended’, ‘shadow’, and ‘debug’. Choose ‘primary’ as the memory access type. Set chip ID address

to ‘addr’, create a numeric array with 0x30 and 0x31, and connect them to corresponding inputs. The read-

Progress is a delegate method that can be used to display a progress dialog, incrementing the progress once

per memory access read. The readProgress can be null if no progress dialog is desired. The returns of this

method are in an array.

Figure 8: Read Chip ID

955 PERIMETER ROAD • MANCHESTER, NH 03103 • USA

+1-603-626-2300 • FAX: +1-603-641-5336 • ALLEGROMICRO.COM

APPLICATION INFORMATION

296186-AN

MCO-0000910

IMPLEMENT SINGLE DIE TRANSFER FUNCTION

To achieve a transfer function as shown in Figure 1, use data from two readings, Position1 and Position2, to calculate

the desired offset and gain values.

There are three main methods used to perform this two-point calculation and to write dedicated values to the device:

TPPLGetPosition1Information, TPPLGetPosition2Information, and TPPLCalculate.

TPPLGetPosition1Information

object TPPLGetPosition1Information (Dictionary<string, object> options, ProgressDone readProgress

This method collects the information for Position1. The following input options can be selected:

Options – can be null

• Count – integer; the number of times the inputs are sampled. Default is 1.

□ It is strongly recommended to sample Position1 more than once. This means it will take more time to

program the A1330. Decide between desired accuracy and time to program A1330.

• Rotation Direction – string; when “cw”, the field is increasing clockwise and PO will be set to 0; when “ccw”,

the field is increasing counterclockwise and PO will be set to 1. Default is “cw”.

□ This is the rotation direction of the magnet, as viewed looking down on the IC with pin 1 positioned in the

top left.

ReadProgress – ProgressDone; a routine that updates a progress bar and can be null if not needed.

Create an invoke node and select ‘TPPLGetPosition1Information’ method. To add ‘options’, follow the procedure below:

1. Create an invoke node and select ‘EmptyOptionsDictionary’ method.

2. Create an invoke node and select ‘SetStringInOptionsDictionary’ method, wire the output of ‘EmptyOption-

sDictionary’ method to ‘options’, set ‘optionName’ as ‘Rotation Direction’, and set ‘optionValue’ to ‘cw’.

After these settings, the magnet can be rotated clockwise only. To rotate the magnet counterclockwise, set

‘optionValue’ to ‘ccw’.

3. Create an invoke node, select ‘SetUnsignedIntegerInOptionsDictionary’ method, set ‘optionName’ as

‘Count’, and set ‘optionValue’ to 1; this value depends on how many times to sample Position1. ‘options’ is

parallel with all ‘options’ wires.

4. Connect wires like Figure 9 to get Object ‘TPPLGetPosition1Information’.

Figure 9: Get Position1 Information

955 PERIMETER ROAD • MANCHESTER, NH 03103 • USA

+1-603-626-2300 • FAX: +1-603-641-5336 • ALLEGROMICRO.COM

APPLICATION INFORMATION

296186-AN

MCO-0000910

TPPLGetPosition2Information

object TPPLGetPosition2Information (Dictionary<string, object> options, ProgressDone readProgress)

This method collects the information for Position2. The following input options can be selected:

Options – Can be Null

• Count – integer; the number of times the inputs are sampled. Default is 1.

□ It is strongly recommended to sample Position2 more than once. This means it will take more time to

program the A1330. Decide between desired accuracy and time to program A1330.

• Rotation Direction – string; when “cw”, the field is increasing clockwise and PO will be set to 0; when “ccw”,

the field is increasing counterclockwise and PO will be set to 1. Default is “cw”.

□ This is the rotation direction of the magnet, as viewed looking down on the IC with pin 1 positioned in the

top left.

ReadProgress – ProgressDone; a routine that updates a progress bar and can be null if not needed.

Create an invoke node and select ‘TPPLGetPosition2Information’ method. To add ‘options’, follow the procedure below:

1. Create an invoke node and select ‘EmptyOptionsDictionary’ method.

2. Create an invoke node and select ‘SetStringInOptionsDictionary’ method, wire the output of ‘EmptyOption-

sDictionary’ method to ‘options’, set ‘optionName’ as ‘Rotation Direction’, and set ‘optionValue’ to ‘cw’.

After these settings, the magnet can be rotated clockwise only. To rotate the magnet counterclockwise, set

‘optionValue’ to ‘ccw’

3. Create an invoke node, select ‘SetUnsignedIntegerInOptionsDictionary’ method, set ‘optionName’ as

‘Count’, and set ‘optionValue’ to 1; this value depends on how many times to sample Position2. ‘options’ is

parallel with all ‘options’ wires.

4. Connect wires like Figure 10 to get Object ‘TPPLGetPosition2Information’.

Figure 10: Get Position2 Information

955 PERIMETER ROAD • MANCHESTER, NH 03103 • USA

+1-603-626-2300 • FAX: +1-603-641-5336 • ALLEGROMICRO.COM

APPLICATION INFORMATION

296186-AN

MCO-0000910

TPPLCalculate

Dictionary<string, uint> TPPLCalculate(object Position1, object Position2, double desiredPosition1,

double desiredPosition2, Dictionary<string, object> options, ProgressDone calculationProgress)

This method takes the position information, the desired positions, and the options and calculates the values. If

desired, these values are written to the device. There are six input parameters, Position1, Position2, desiredPosi-

tion1, desiresPosition2, options, and calculationProgress.

• Position1 – the data returned from the TPPLGetPosition1Information method.

• Position2 – the data returned from the TPPLGetPosition2Information method.

• desiredPosition1 – the desired value for position 1. The units and value will depend on “Output Units”.

• desiresPosition2 – the desired value for position 2. The units and value will depend on “Output Units”.

• options –

□ Rotation Direction – String; when “cw” the field is increasing clockwise and PO will be set to 0; when “ccw”

the field is increasing counterclockwise and PO will be set to 1. Default is “cw”.

□ Minimum Input Angle – Double; the units and value will depend on “Input Units”. Default is 0.

□ Maximum Input Angle – Double; the units and value will depend on “Input Units”. Default is maximum value.

□ Low Clamp Value – Double; the units and value will depend on “Output Units”. Default is 0.

□ High Clamp Value – Double; the units and value will depend on “Output Units”. Default is maximum value.

□ Post Gain Offset Value – Double; the units and value will depend on “Input Units”. Default is 0.

□ Clamp Enable – Boolean; when true, the field “CE” will be set. Default is false.

□ Rollover Enable – Boolean; when true, the field “ROE” will be set. Default is false.

□ Write to Chip – Boolean; false disables writing the calculated values to the device, default is true.

□ Input Units – String; default is “degrees”.

◦ “degrees” – all of the values are in degrees (0 to 360).

◦ “percentage” – all of the values are in percentage (0 to 100).

◦ “bams” – all of the values are between 0 and 4095 inclusively.

□ Output Units – String; default is “degrees”.

◦ “degrees” – all of the values are in degrees (0 to 360).

◦ “volts” – all of the values are in volts (0 to 5.0).

◦ “duty cycle” – all of the values are in percentage (0 to 100).

◦ “percentage” – all of the values are in percentage (0 to 100).

◦ “bams” – all of the values are between 0 and 4095 inclusively.

□ Diagnostics – when this option is present, the internal diagnostics are enabled and returned as a string in

this option.

• calculationProgress – ProgressDone; a routine that updates a progress bar and can be null if not needed.

Figure 11: Calculate two-point parameters and write them to A1330.

955 PERIMETER ROAD • MANCHESTER, NH 03103 • USA

+1-603-626-2300 • FAX: +1-603-641-5336 • ALLEGROMICRO.COM

APPLICATION INFORMATION

296186-AN

MCO-0000910

Create an invoke node, select ‘TPPLCalculate’ method and fill arguments following below procedures:

1. Connect Object ‘TPPLGetPosition1Information’ and Object ‘TPPLGetPosition2Information’ which are imple-

mented in Figure 9 and Figure 10 to corresponding inputs, as shown in Figure 11.

2. Create two oat constants with ‘0.5’ and ‘4.5’ and wire them to ‘desiredPosition1’ and ‘desiredPosition2’ as

in Figure 11.

3. Create invoke node with related method to ll the ‘options’ of TPPLCalculate(), if desired. The methods

that are used depend on the type of optionValue. For example, to change the output units from default

value (degrees) to voltages, select ‘SetStringInOptionsDictionary’ for this method and wire a string constant

named ‘volts’, as shown in Figure 11.

4. Some options must be noted to achieve the curve in Figure 1:

• Set ‘Low Clamp value’ to 0.5, which means the curve is clamped to 0.5 V at minimum.

• Set ‘High Clamp value’ to 4.5, which means the curve is clamped to 4.5 V at maximum.

• Set ‘Post Gain Offset Value’ to 10, which provides 10 degrees headroom before Position1 to stay low clamp

value.

• Set ‘Clamp Enable’ to True, enabling clamp function of A1330.

5. If desired, set ‘FineTune’ to True or False to tradeo between accuracy and time to program A1330.

At this point, all functions have been introduced. The next step depends on how these methods will be used to make

the mass production programmer. An example is given in the flowchart below:

Figure 12: Two points programing Flow Chart in LabVIEW.

The flowchart above can be modified based on application requirements.

Now when moving the magnet from Position1 to Position2, the transfer function of Figure 1 should appear.

955 PERIMETER ROAD • MANCHESTER, NH 03103 • USA

+1-603-626-2300 • FAX: +1-603-641-5336 • ALLEGROMICRO.COM

APPLICATION INFORMATION

296186-AN

MCO-0000910

IMPLEMENT DUAL DIE TRANSFER FUNCTION

If the A1330 dual die version is to be used to make curves like Figure 2 and Figure 3, the following procedure is

suggested, based on ASEK-21:

Figure 13: Implement Dual Die Transfer Function in LabVIEW.

Most functions and methods used in this flowchart have been stated previously, except how to switch dies.

On ASEK-20, use SetDieSelection (int die) to set which die the DLL will communicate. The input should be

0 or 1.

On ASEK-21, use SetASEK21Port (uint port) to set which port to use for ASEK-20 device commands. Port must be

a value between 1 and 4. Refer to article about how to connect A1330 and ASEK-21 on the Allegro software website.

955 PERIMETER ROAD • MANCHESTER, NH 03103 • USA

+1-603-626-2300 • FAX: +1-603-641-5336 • ALLEGROMICRO.COM

APPLICATION INFORMATION

296186-AN

MCO-0000910

CONCLUSION

Customers can perform two-point programming in LabVIEW following the procedures and flowcharts in this applica-

tion note. With the Allegro Programmer ASEK-21, it is simple to support customer applications in mass production,

such as throttle position, acceleration/brake pedal position, and other short-stroke (<360° rotation) applications.

To learn more information about the A1330 DLL and code examples written in C# language, refer to ‘Program-

ming_the_A1330_using_the_ASEK_DLLs’ article on Allegro software website.

955 PERIMETER ROAD • MANCHESTER, NH 03103 • USA

+1-603-626-2300 • FAX: +1-603-641-5336 • ALLEGROMICRO.COM

APPLICATION INFORMATION

296186-AN

MCO-0000910

The information contained in this document does not constitute any representation, warranty, assurance, guaranty,

or inducement by Allegro to the customer with respect to the subject matter of this document. The information being

provided does not guarantee that a process based on this information will be reliable, or that Allegro has explored

all of the possible failure modes. It is the customer’s responsibility to do sufficient qualification testing of the final

product to insure that it is reliable and meets all design requirements.

Copies of this document are considered uncontrolled documents.

Revision History

Number Date Description Responsibility

– July 9, 2020 Initial release J. Zhao