Analog Stick Data

10min

Decode Joystick Data
This is a section detailing how to interpret analog/joystick data coming from the controller.
Slow Mode/Short Input Report Joystick Data
Starting on byte 4 of the incoming report from the controller, you can find the joystick analog data encoded as follows.
Byte Number
Description
Example Data
4
Lower byte of X axis
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5
Upper byte of X axis
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6
Lower byte of Y axis
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7
Upper byte of Y axis
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To get values for the right stick, add 4 to the byte index.
To get the X or Y axis values, OR the respective bytes together.
C++
|
X_Axis = byte[4] | (byte[5] << 8);
Y_Axis = byte[6] | (byte[7] << 8);
X_Axis = byte[4] | (byte[5] << 8);
Y_Axis = byte[6] | (byte[7] << 8);
﻿
Standard Input Mode Joystick Data
Starting on byte 6 of a standard input mode report from the controller, you can find the joystick analog data encoded as follows.
Byte Number
Description
Example Data
6
Lower byte of X axis. 8 bits.
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7
Lower 4 bits are the Upper byte of X axis. Upper 4 bits are the lower byte of the Y axis
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8
Upper byte of Y axis. 8 bits.
﻿
For the right stick, add 3 to the byte index.
To get the decoded X or Y axis values, some math is involved. 
C++
|
X_Axis = byte[6] | ((byte[7] & 0xF) << 8);
Y_Axis = (byte[7] >> 4) | (byte[8] << 4);
X_Axis = byte[6] | ((byte[7] & 0xF) << 8);
Y_Axis = (byte[7] >> 4) | (byte[8] << 4);
﻿
Encode Joystick Data
This section details how to take an analog stick value and encode it to be read by the console.
Slow Mode Joystick Data
In a standard input report, bytes 4-7 represent the stick data.
For this example, we will use these values and we will only focus on the left stick which is bytes 4-5.
X axis - 0x7D4 (2004 in decimal)
Y axis - 0x6C5 (1733 in decimal)
C++
|
uint8_t input_bytes[4];

uint16_t x_axis = 0x7D4;
uint16_t y_axis = 0x6C5;

// Trim off the top bits.
input_bytes[0] = x_axis & 0xFF;

// Take only the uppermost byte of x_axis and shift right 8 bits.
input_bytes[1] = (x_axis & 0xF00) >> 8;

// Trim off the top bits.
input_bytes[2] = y_axis & 0xFF;

// Take only the uppermost byte of y_axis and shift right 8 bits.
input_bytes[3] = (y_axis & 0xF00) >> 8;

// Final results
// 0 - 0xD4
// 1 - 0x07
// 2 - 0xC5
// 3 - 0x06
uint8_t input_bytes[4];

uint16_t x_axis = 0x7D4;
uint16_t y_axis = 0x6C5;

// Trim off the top bits.
input_bytes[0] = x_axis & 0xFF;

// Take only the uppermost byte of x_axis and shift right 8 bits.
input_bytes[1] = (x_axis & 0xF00) >> 8;

// Trim off the top bits.
input_bytes[2] = y_axis & 0xFF;

// Take only the uppermost byte of y_axis and shift right 8 bits.
input_bytes[3] = (y_axis & 0xF00) >> 8;

// Final results
// 0 - 0xD4
// 1 - 0x07
// 2 - 0xC5
// 3 - 0x06
﻿
Standard Input Mode Joystick Data
In a standard input report, bytes 6-11 represent the stick data.
For this example, we will use these values and we will only focus on the left stick which is bytes 6-8.
X axis - 0x7D4 (2004 in decimal)
Y axis - 0x6C5 (1733 in decimal)
C++
|
uint8_t input_bytes[3];

uint16_t x_axis = 0x7D4;
uint16_t y_axis = 0x6C5;

// Trim off the top byte.
input_bytes[0] = x_axis & 0xFF;

// Take only the uppermost 4 bits of x_axis (0x7).
input_bytes[1] = x_axis >> 8;

// Add the lowermost 4 bits of y_axis shifted 4 bits
// to the proper position (0x5).
input_bytes[1] |= (y_axis & 0xF) << 4;

// Take only the uppermost byte of y_axis (0x6C).
input_bytes[2] = y_axis >> 4;

// Final results
// 0 - 0xD4
// 1 - 0x57
// 2 - 0x6C
uint8_t input_bytes[3];

uint16_t x_axis = 0x7D4;
uint16_t y_axis = 0x6C5;

// Trim off the top byte.
input_bytes[0] = x_axis & 0xFF;

// Take only the uppermost 4 bits of x_axis (0x7).
input_bytes[1] = x_axis >> 8;

// Add the lowermost 4 bits of y_axis shifted 4 bits
// to the proper position (0x5).
input_bytes[1] |= (y_axis & 0xF) << 4;

// Take only the uppermost byte of y_axis (0x6C).
input_bytes[2] = y_axis >> 4;

// Final results
// 0 - 0xD4
// 1 - 0x57
// 2 - 0x6C
﻿
﻿

Updated 03 Mar 2023

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TABLE OF CONTENTS

Decode Joystick Data

Slow Mode/Short Input Report Joystick Data

Standard Input Mode Joystick Data

Encode Joystick Data

Slow Mode Joystick Data

Standard Input Mode Joystick Data

Byte Number	Description	Example Data
4	Lower byte of X axis
5	Upper byte of X axis
6	Lower byte of Y axis
7	Upper byte of Y axis