Logitech joystick connected to Arduino
HID report parsing explained in the previous article works pretty well with properly aligned HID reports. The analog controls are placed on a byte or word boundary and buttons occupy dedicated fields. The majority of HID devices are designed this way, however, some other devices are not that simple to interface and today I’m going to show how to handle one of those.
A Logitech Extreme 3D Pro joystick is one nice HID device. It is good looking, well-built, and have a twist handle, which adds third axis to a stick making this model popular among FPV fliers since you can control pitch, roll and yaw with one hand. Also, X and Y axis are 10 bits which gives good precision. There is one problem with this joystick – its input report.
Logitech, in its infinite wisdom, decided to pack all the high and low resolution analog controls plus 12 buttons in 6 bytes of input report. The report looks like this – 10 bits of X, 10 bits of Y, and 4 bits of hat switch. After that, things become easier – one byte of Rz AKA “twist handle”, one byte of buttons, one byte of throttle (called “slider” in the report), and finally, one partially filled byte holding the rest of the buttons. Take a look at the screenshot below – two most important controls are not byte aligned, therefore, simple straightforward parsing of the report is not possible. Also, USBHID_descr won’t show this report correctly.
To demonstrate how to deal with this report I wrote a simple Arduino sketch. It was made by modifying an example from the previous article. I also made it as simple as possible – as soon as any of the controls changes its value, new report is printed on the serial terminal. The sample output is shown below followed by code explanation.
Start HU Init Addr:1 NC:1 Cnf:1 HU configured Buf: FCF18780000000 X: 01FC Y: 01FC Hat Switch: 08 Twist: 80 Slider: 00 Buttons A: 00 Buttons B: 00 Buf: FCF18780000200 X: 01FC Y: 01FC Hat Switch: 08 Twist: 80 Slider: 02 Buttons A: 00 Buttons B: 00 Buf: FCF18783000200 X: 01FC Y: 01FC Hat Switch: 08 Twist: 83 Slider: 02 Buttons A: 00 Buttons B: 00 Buf: FCF18786000200 X: 01FC Y: 01FC Hat Switch: 08 Twist: 86 Slider: 02 Buttons A: 00 Buttons B: 00 |
The first important piece of the code is the report representation. To be able to access every control the following structure has been declared – compare it with the screenshot produced by my trusty Totalphase Beagle USB protocol analyzer:
struct GamePadEventData { union { //axes and hut switch uint32_t axes; struct { uint32_t x : 10; uint32_t y : 10; uint32_t hat : 4; uint32_t twist : 8; }; }; uint8_t buttons_a; uint8_t slider; uint8_t buttons_b; }; |
Logitech input report
The
Parse() method works similarly to the original code – it receives the report from the device and compares it with the stored copy of the previous reading. If reports are different, OnGamePadChanges() is called, which simply prints the report on the terminal. It can easily be modified to do something useful like change PWM pulse width to control motor speed, servo pulse or generate analog signal.
void JoystickReportParser::Parse(HID *hid, bool is_rpt_id, uint8_t len, uint8_t *buf) { bool match = true; // Checking if there are changes in report since the method was last called for (uint8_t i=0; i<RPT_GAMEPAD_LEN; i++) { if( buf[i] != oldPad[i] ) { match = false; break; } } // Calling Game Pad event handler if (!match && joyEvents) { joyEvents->OnGamePadChanged((const GamePadEventData*)buf); for (uint8_t i=0; i<RPT_GAMEPAD_LEN; i++) oldPad[i] = buf[i]; } } |
This simple technique is very helpful when dealing with awkward reports. If you need help with parsing output from your HID reports or would like to see more detailed explanation of the code, please let me know.
Oleg.
Great info! I was easily able to use this article and Developing Arduino
code for HID Joystick to get my Logitech Attack 3 working with a
simple structure update.
// Logitech Attack 3 Joystick 5 bytes
struct GamePadEventData
{
uint8_t x;
uint8_t y;
uint8_t slider;
uint8_t buttons_1to8;
uint8_t buttons_9to11;
};
Hi, I used V1 usb host shield with Saitek X45 and all was ok.
Now i try on ADK and de len report is 11 Bytes but he cut at 8.
I show you the desciptor! could you help me?
Start
HU Init
Addr:1
NC:1
Cnf:1
HU configured
0000: 05 01 09 04 A1 01 09 30 16 00 00 26 FF 0F 75 0C
0010: 95 01 81 02 09 31 16 00 00 26 FF 0F 75 0C 95 01
0020: 81 02 09 36 15 00 26 FF 00 75 08 95 01 81 02 09
0030: 35 15 00 26 FF 00 75 08 95 01 81 02 09 37 15 00
0040: 26 FF 00 75 08 95 01 81 02 09 33 15 00 26 FF 00
0050: 75 08 95 01 81 02 05 09 15 00 25 01 19 01 29 1A
0060: 75 01 95 1A 81 02 75 02 95 01 81 01 05 01 09 39
0070: 15 01 25 08 35 00 46 3B 01 66 14 00 75 04 95 01
Usage Page Gen Desktop Ctrls(01)
Usage Game Pad
Collection Application
Usage X
Logical Min(0000)
Logical Max(FF0F)
Report Size(0C)
Report Count(01)
Input(00000010)
Usage Y
Logical Min(0000)
Logical Max(FF0F)
Report Size(0C)
Report Count(01)
Input(00000010)
Usage Slider
Logical Min(00)
Logical Max(FF00)
Report Size(08)
Report Count(01)
Input(00000010)
Usage Rz
Logical Min(00)
Logical Max(FF00)
Report Size(08)
Report Count(01)
Input(00000010)
Usage Dial
Logical Min(00)
Logical Max(FF00)
Report Size(08)
Report Count(01)
Input(00000010)
Usage Rx
Logical Min(00)
Logical Max(FF00)
Report Size(08)
Report Count(01)
Input(00000010)
Usage Page Button(09)
Logical Min(00)
Logical Max(01)
Usage Min(01)
Usage Max(1A)
Report Size(01)
Report Count(1A)
Input(00000010)
Report Size(02)
Report Count(01)
Input(00000001)
Usage Page Gen Desktop Ctrls(01)
Usage Hat Switch
Logical Min(01)
Logical Max(08)
Physical Min(00)
Physical Max(3B01)
Unit(1400)
Report Size(04)
Report Count(01)
Buf: 9EE0085CB1515200
Game Pad X(E0)
Y(E8)
Slider(5C)
Rz(B1)
Dial(9E)
Rx(0E)
Btn1(00) Btn2(00) Btn3(00) Btn4(01) Btn5(00) Btn6(00) Btn7(00) Btn8(00) Btn9(00) BtnA(00) BtnB(01) BtnC(01) BtnD(01) BtnE(00) BtnF(01) Btn10(00) Btn11(01) Btn12(00) Btn13(00) Btn14(00) Btn15(01) Btn16(01) Btn17(00) Btn18(01) Btn19(01) Btn1A(00)
(00)
Hat Switch
Buf: 0C0000
Game Pad X(C0)
Y(00)
Slider(00)
Rz(00)
Dial(0C)
Rx(00)
Btn1(00) Btn2(00) Btn3(00) Btn4(00) Btn5(00) Btn6(00) Btn7(00) Btn8(00) Btn9(00) BtnA(00) BtnB(00) BtnC(00) BtnD(00) BtnE(00) BtnF(00) Btn10(00) Btn11(00) Btn12(00) Btn13(00) Btn14(00) Btn15(00) Btn16(00) Btn17(00) Btn18(00) Btn19(00) Btn1A(00)
(00)
Hat Switch
Hi all – and thanks Oleg for a great shield and library! I know i am replying to an old question here but i had a similar problem with version 2 of the library that i found a solution to that i wanted to share. In my case i have a Microsoft wireless mobile mouse 3000 for which i was receiving a cut off HID report in report mode (not boot!) in the sample USBHID_desc as well as in my own code – as per described by Sisco.
Basically the issue is down to this device having a particularly long hid report, so this will be true for any device with a long HID report. I tracked the problem down to a hard coded value in the HID.cpp USB library code for GetReportDescr.
Here is the code – the pUsb->ctrlReq call has the 8th parameter value set to 128 which limits the max length of the hid report:
int8_t HID::GetReportDescr( uint8_t ep, USBReadParser *parser )
{
const uint8_t constBufLen = 64;
uint8_t buf[constBufLen];
uint8_t rcode = pUsb->ctrlReq( bAddress, ep, bmREQ_HIDREPORT, USB_REQUEST_GET_DESCRIPTOR, 0x00,
HID_DESCRIPTOR_REPORT, 0x0000, 128, constBufLen, buf, (USBReadParser*)parser );
//return ((rcode != hrSTALL) ? rcode : 0);
return rcode;
}
If like me you find your hid report terminates too early, increase the parameter value from 128. For my mouse I had to up to 320 and the HID report now gets returned complete. Hope this helps.
THX
Andy
You mean your _report_ is that long? I’ve seen report descriptors which were quite large but not reports themselves.
Yes seems petty long for what seems a basic mouse with wheel!!
For interest here is the full USBHID_desc output:
HU configured
0000: 05 0C 09 01 A1 01 05 01 09 02 A1 02 85 13 05 0C
0010: 0A 38 02 95 01 75 08 15 81 25 7F 81 06 85 14 06
0020: 00 FF 0A 01 FE 75 02 15 00 25 03 81 02 0A 02 FE
0030: 0A 00 FE 95 02 75 01 25 01 81 02 0A 03 FF 95 01
0040: 75 02 25 03 81 02 81 01 85 15 75 01 25 01 0A 0B
0050: FF 81 02 75 07 81 01 0A 0D FF 75 10 27 FF FF 00
0060: 00 81 02 85 17 0A 06 FF 0A 0F FF 25 01 35 01 45
0070: 10 95 02 75 02 B1 02 0A 04 FF 35 00 45 00 95 01
0080: 75 01 B1 02 75 03 B1 01 C0 C0 05 01 09 02 A1 01
0090: 05 01 09 02 A1 02 85 11 09 01 A1 00 05 09 19 01
00A0: 29 05 95 05 75 01 25 01 81 02 75 03 95 01 81 01
00B0: 05 01 09 30 09 31 95 02 75 08 15 81 25 7F 81 06
00C0: A1 02 85 12 09 48 95 01 75 02 15 00 25 01 35 01
00D0: 45 10 B1 02 85 11 09 38 35 00 45 00 15 81 25 7F
00E0: 75 08 81 06 C0 A1 02 85 12 09 48 75 02 15 00 25
00F0: 01 35 01 45 10 B1 02 35 00 45 00 75 04 B1 01 85
0100: 11 05 0C 15 81 25 7F 75 08 0A 38 02 81 06 C0 C0
0110: C0 C0
Usage Page Consumer(0C)
Usage Consumer Ctrl
Collection Application
Usage Page Gen Desktop Ctrls(01)
Usage Mouse
Collection Logical
Report Id(13)
Usage Page Consumer(0C)
Usage AC Mir H
Report Count(01)
Report Size(08)
Logical Min(81)
Logical Max(7F)
Input(00000110)
Report Id(14)
Usage Page Undef(00)
Usage
Report Size(02)
Logical Min(00)
Logical Max(03)
Input(00000010)
Usage
Usage
Report Count(02)
Report Size(01)
Logical Max(01)
Input(00000010)
Usage
Report Count(01)
Report Size(02)
Logical Max(03)
Input(00000010)
Input(00000001)
Report Id(15)
Report Size(01)
Logical Max(01)
Usage
Input(00000010)
Report Size(07)
Input(00000001)
Usage
Report Size(10)
Logical Max(FFFF0000)
Input(00000010)
Report Id(17)
Usage
Usage
Logical Max(01)
Physical Min(01)
Physical Max(10)
Report Count(02)
Report Size(02)
Feature(00000010)
Usage
Physical Min(00)
Physical Max(00)
Report Count(01)
Report Size(01)
Feature(00000010)
Report Size(03)
Feature(00000001)
End Collection
End Collection
Usage Page Gen Desktop Ctrls(01)
Usage Mouse
Collection Application
Usage Page Gen Desktop Ctrls(01)
Usage Mouse
Collection Logical
Report Id(11)
Usage Pointer
Collection Physical
Usage Page Button(09)
Usage Min(01)
Usage Max(05)
Report Count(05)
Report Size(01)
Logical Max(01)
Input(00000010)
Report Size(03)
Report Count(01)
Input(00000001)
Usage Page Gen Desktop Ctrls(01)
Usage X
Usage Y
Report Count(02)
Report Size(08)
Logical Min(81)
Logical Max(7F)
Input(00000110)
Collection Logical
Report Id(12)
Usage Res Mult
Report Count(01)
Report Size(02)
Logical Min(00)
Logical Max(01)
Physical Min(01)
Physical Max(10)
Feature(00000010)
Report Id(11)
Usage Wheel
Physical Min(00)
Physical Max(00)
Logical Min(81)
Logical Max(7F)
Report Size(08)
Input(00000110)
End Collection
Collection Logical
Report Id(12)
Usage Res Mult
Report Size(02)
Logical Min(00)
Logical Max(01)
Physical Min(01)
Physical Max(10)
Feature(00000010)
Physical Min(00)
Physical Max(00)
Report Size(04)
Feature(00000001)
Report Id(11)
Usage Page Consumer(0C)
Logical Min(81)
Logical Max(7F)
Report Size(08)
Usage AC Mir H
Input(00000110)
End Collection
End Collection
End Collection
End Collection
i’m doing that but is still cutting at the 8th value… do you suppose to do something else in the arduino code? all I have is set to uint8_t, is that ok?
Hi guys,
thanks for the work you did, im very aprichiate about your homepage!
i hav estill some questions about the usb host 2 library. im using a microsoft sidewinder with my arduino mega adk. everything is working fine. im getting good rrsults in the serial monitorlike
Buf: 08EDFF0F0040X: 08 Y: ED Z: FF Z: 0F Rz: 00
Buf: 08EDFFEF0340
X: 08 Y: ED Z: FF Z: EF Rz: 03
Buf: 08EDFF0F0040
X: 08 Y: ED Z: FF Z: 0F Rz: 00
but unfortunately i dont know how to get something different modified like you said ” It can easily be modified to do something useful like change PWM pulse width to control motor speed, servo pulse or generate analog signal.” i tried to find something how can i modify f.e. motors with pwn. can you say me please how i work with these datas?
best from big berlin
ben
Sometimes, it was not able to start with logitech Extreme 3D pro. The program stopped after print “NC:1”.
How do you power it?
I use a USB 2.0 cable (from PC) to power my Arduino UNO.(Joystick was already plugged in the USB shield)
The joystick program can easily start up when I plug Mouse or Keyboard in USB Shield. =_=||
The USB ports of my PC are all USB3.0 port, and the USB2.0 cable from PC to UNO is short(about 30cm).
So, I think the power is enough.
Are you finished talking?
I reset or power the UNO, and then shake the joystick quickly immediately.
Do it like this, the probability of “start up successful” is high.
I finished talking.
Thanks.
Try using external power supply, 9-12V, connected to UNO round connector port.
I tryed BETOP BTP-4328 and Thrustmaster T16000M, and they all worked well with the Arduino USB Shield 2.0. It seems that there is something wrong with my Extreme 3D pro, although the joystick works well with my computer.
(Maybe the reason is that all of the Extreme 3D pro joysticks in China are cost-down version….)
THX
Hello!
Could you please help me to find info about how to connect and interact between Logitech Wireless Gamepad F710 and ArduinoUno + USB Host Shield?
Thank you.
I recently have logitech F710 . My usb host shild 2.0 just arrived yesterday from my local seller. I put it on my uno and then upload with the sample sketch for hidjoystick it not work at first but i manage to have it work with following steps
1. Plug the reciever to a pc
2. Install the gaming control software came with the f710 follow the installation until the joystick testing is display and confirm the joystck is working properly.
3 switch the joystick mode switch to ‘D’ mode yhen test it again on pc. I try it with mode ‘X’ on the hostshield but it seem to not working i not try with the xbox sample yet it probably work as well.
4 unplug the reciever from pc them put it on the usb hostshield then plug the arduino on o the pc usb port open the serial monitor in the arduino ide.
5. The sample just work without any modification. It will display start then immediately display the buttons status that was pressed in the serial monitor.
Ther is no need to do connection between the reciever and the joystick because it have been sync during the test perform on the pc and it will stay connected.
Hope this help
I have a sainsmart mega 2560 and sainsmart usb 2.0 board and a logitech extreme 3d joystick.
I have the latest from master github branch.
When I run the sketch on it it just says Start and doesn’t repsond to key presses. If I do as newwzp did by resetting several times then it responded – once.
I have tried with both external power from my sabertooth and without external power.
If I run USBHID_Desc it does the same thing.
If I run USC_desc I get the following report, with no more output than than. –
Start
01
—
Device descriptor:
Descriptor Length: 12
Descriptor type: 01
USB version: 0110
Device class: 00
Device Subclass: 00
Device Protocol: 00
Max.packet size: 08
Vendor ID: 046D
Product ID: C215
Revision ID: 0204
Mfg.string index: 01
Prod.string index: 02
Serial number index: 00
Number of conf.: 01
Configuration descriptor:
Total length: 0022
Num.intf: 01
Conf.value: 01
Conf.string: 00
Attr.: 80
Max.pwr: 0F
Interface descriptor:
Intf.number: 00
Alt.: 00
Endpoints: 01
Intf. Class: 03
Intf. Subclass: 00
Intf. Protocol: 00
Intf.string: 00
Unknown descriptor:
Length: 09
Type: 21
Contents: 10012101227A000705
Endpoint descriptor:
Endpoint address: 81
Attr.: 03
Max.pkt size: 0007
Polling interval: 0A
Addr:1(0.0.1)
FYI – I finally got my Logitech Extreme 3D Pro joystick to working!!
Found this link – his version of the code works for me and my mega and usb host 2.0 – I am getting data in serial monitor and it looks correct.
HIS webpage is here –
http://www.ianjohnston.com/index.php?option=com_content&view=article&id=79
Close to bottom of page he says he fixed the bug –
HIS Joystick code – havent tried yet 0
http://www.ianjohnston.com/images/stories/IanJ/JoystickV3/code/RCJoystickTx_USB_LE3DP_ArdMega_IDEV1_V8_76.zip
HIS library –
http://www.ianjohnston.com/images/stories/IanJ/JoystickV3/code/USBHostShield2.zip
Can also be found here – http://www.rcgroups.com/forums/showthread.php?t=1704110
I need to know how to get the report values from the CPP file into the sketch. I know inside the loop after the usb.task….but how to access – (evt->x), (evt->y), (evt->twist)….etc…
I am wanting to use values to run 2 servos – sabertooth…..
any help appreciated…
You can access
GamePadEventDatastructure. Just make sure you don’t blockUsb.Task(). Alternatively, modifyJoystickEvents::OnGamePadChangedto do what you need instead of printing.Can you give us an example of how to do this inside loop()? Everything I try, it says I don’t have access in this scope.
Thanks!
You need to modify existing parser to copy received data to a global variable. You can then access this var from anywhere.
How do I get the evt-> x, evt-> y … the sketch in arguivo. ino. I am trying to pass this data to a radio controller.
I have a Logitech Extreme 3D, Uno and your USBHost shield and I installed your sketch and USBHost 2.0 library and it seems to work, but when I monitor activity on the serial monitor, I see a constant stream of stuff that doesn’t appear to be from your code that fills the time between stick events. There’s a snippet below from the end of the initialization. The Address, EP, NAK Power and NAK Limit messages are constantly streaming past and I’m wondering if there’s a way to suppress this chatter that’s unrelated to the joystick? Is this part of the USB handshaking?
Thanks
Buf: 0002888000CE00
X: 0200 Y: 0200 Hat Switch: 08 Twist: 80 Slider: CE Buttons A: 00 Buttons B: 00
Address: 1
EP: 1
NAK Power: 1
NAK Limit: 1
Address: 1
EP: 1
NAK Power: 1
NAK Limit: 1
Address: 1
EP: 1
NAK Power: 1
NAK Limit: 1
Address: 1
EP: 1
NAK Power: 1
NAK Limit: 1
Address: 1
EP: 1
NAK Power: 1
NAK Limit: 1
Address: 1
EP: 1
NAK Power: 1
NAK Limit: 1
Hello there. I am trying to use an Arduino Uno to control Victor 888’s and power four CIMs. At this point I know how to use servo code to make the Victors work, the only thing is that I need to get the code to read joystick values. In RobotC I can just include the #include.”joystick.driver”; and have it work. However in Arduino I don’t know how to get the UNO to prompt my laptop for old or new joystick values, therefore making me unable to create variables and integers in the code to modify servo speed values. Help? ALSO I for now am just plugging the joystick into the computer and connecting the arduino into the PC.
Thanks for the library. I had a couple of Logitec Pro joysticks that got fried somehow on an XP box. I was able to use the HID example sketch le3dp to confirm which inputs were bad … sigh. I used a sparkfun USB host shield, and that required jumpers to pins 10-13, a pin 7 to RESET jumper, and to get the joystick to respond, I needed 7.5v to DC input jack on 2560 board. All that finally worked!
I have tried the Arduino Sketch from the link above and it fails to compile on three different Arduinos. Is this the current sketch?
Thanks so much!
Doyle
It won’t depend on the board but rather how you set up the library. Were you able to compile any of USB host code examples?
What is the baud rate of the logitech attack 3 joustick?
i just need a very simple example allow me to turn on ro off a led using any button
thanx
i’m getting all data the right way but i don know how to use it actually i can’t understand what exactly are the variables names so i cant call it or use it and this is what i get through serial monitoring (i’m using logitech 3d force)
X: 02D2 Y: 0212 Hat Switch: 08 Twist: 80 Slider: FF Buttons A: 00 Buttons B: 00
X: 025E Y: 0212 Hat Switch: 08 Twist: 80 Slider: FF Buttons A: 01 Buttons B: 00
X: 0204 Y: 023A Hat Switch: 08 Twist: 80 Slider: FF Buttons A: 01 Buttons B: 00
X: 01B7 Y: 023A Hat Switch: 08 Twist: 80 Slider: FF Buttons A: 01 Buttons B: 00
X: 018F Y: 023A Hat Switch: 08 Twist: 80 Slider: FF Buttons A: 01 Buttons B: 00
X: 017B Y: 023A Hat Switch: 08 Twist: 80 Slider: FF Buttons A: 00 Buttons B: 00
X: 0171 Y: 023A Hat Switch: 08 Twist: 80 Slider: FF Buttons A: 00 Buttons B: 00
X: 01B1 Y: 023A Hat Switch: 08 Twist: 80 Slider: FF Buttons A: 00 Buttons B: 00
X: 01C9 Y: 023A Hat Switch: 08 Twist: 80 Slider: FF Buttons A: 00 Buttons B: 00
X: 01E1 Y: 023A Hat Switch: 08 Twist: 80 Slider: FF Buttons A: 00 Buttons B: 00
X: 01EF Y: 023A Hat Switch: 08 Twist: 80 Slider: FF Buttons A: 02 Buttons B: 00
X: 0202 Y: 023A Hat Switch: 08 Twist: 80 Slider: FF Buttons A: 02 Buttons B: 00
X: 0202 Y: 023A Hat Switch: 08 Twist: 80 Slider: FF Buttons A: 03 Buttons B: 00
X: 0202 Y: 023A Hat Switch: 08 Twist: 80 Slider: FF Buttons A: 02 Buttons B: 00
X: 0202 Y: 0242 Hat Switch: 08 Twist: 80 Slider: FF Buttons A: 00 Buttons B: 00
X: 0202 Y: 0258 Hat Switch: 08 Twist: 80 Slider: FF Buttons A: 00 Buttons B: 00
X: 0202 Y: 0278 Hat Switch: 08 Twist: 80 Slider: FF Buttons A: 03 Buttons B: 00
X: 0202 Y: 027A Hat Switch: 08 Twist: 80 Slider: FF Buttons A: 03 Buttons B: 00
X: 0202 Y: 027A Hat Switch: 08 Twist: 80 Slider: FF Buttons A: 01 Buttons B: 00
so i’m just asking for a simple code that allow me to use (Buttons A and Buttons B) to turn ON and OFF LED
I have a Logitech F310 USB wired gamepad. The USBHID_desc sketch shows following:
Start
0000: 05 01 09 04 A1 01 A1 02 75 08 95 04 15 00 26 FF
0010: 00 35 00 46 FF 00 09 30 09 31 09 32 09 35 81 02
0020: 75 04 95 01 25 07 46 3B 01 65 14 09 39 81 42 65
0030: 00 75 01 95 0C 25 01 45 01 05 09 19 01 29 0C 81
0040: 02 06 00 FF 75 01 95 10 25 01 45 01 09 01 81 02
0050: C0 A1 02 75 08 95 07 46 FF 00 26 FF 00 09 02 91
0060: 02 C0 C0
Usage Page Gen Desktop Ctrls(01)
Usage Game Pad
Collection Application
Collection Logical
Report Size(08)
Report Count(04)
Logical Min(00)
Logical Max(FF00)
Physical Min(00)
Physical Max(FF00)
Usage X
Usage Y
Usage Z
Usage Rz
Input(00000010)
Report Size(04)
Report Count(01)
Logical Max(07)
Physical Max(3B01)
Unit(14)
Usage Hat Switch
Input(01000010)
Unit(00)
Report Size(01)
Report Count(0C)
Logical Max(01)
Physical Max(01)
Usage Page Button(09)
Usage Min(01)
Usage Max(0C)
Input(00000010)
Usage Page Undef(00)
Report Size(01)
Report Count(10)
Logical Max(01)
Physical Max(01)
Usage
Input(00000010)
End Collection
Collection Logical
Report Size(08)
Report Count(07)
Physical Max(FF00)
Logical Max(FF00)
Usage
Output(00000010)
End Collection
End Collection
I have a couple of questions. If I look at the raw data (last parameter uint8_t *buf) to JoystickReportParser::Parse function, it consists of eight bytes, but the last two of them never changes and I am missing some things. I tried to open the gamepad and I see that the two joysticks, right trigger and left trigger (both lower button on front) are analog. The USBHIDJoystick code treats the triggers as analog and has only 8bit resolution on each joystick axis. With SharpDX I have 8bit resolution on the triggers and 16bit on each joystick axis. I tried to look into the “Device Class Definition for Human Interface Devices (HID)” and “HID Usage Tables” but I can’t see the “connection” to my HIDUSB_desc report. One of the bytes in the uint8_t *buf is encoding the Dpad int the lower four bits and the X, Y, A and B buttons upper four bits. The X, Y, A and B buttons are straight forward corresponding to one bit each and just adds up, if more than one is pressed. The Dpad is different – when no buttons are pushed the value is 1000, up = 0000, right = 0010, down = 0100, left = 0110. If up and right is pressed simultaneously the value is 0001 (seems to be (up + right) / 2 ). And the if all four directions are pressed the output is like up + right.
There is a switch on the back on the gamepad to switch between Direct and X input. With this arduino code only the direct input works and with SharpDX only X input works.
Does this difference impact the trigger and joystick resolution?
Can I parse the data from the gamepad so that the raw data to the JoystickReportParser::Parse function has full resolution on trigger and joystick and a more logical encoding of the Dpad buttons?
Nice work! Just a mistake when you said “Logitech, in its infinite wisdom, decided to pack all the high and low resolution analog controls plus 12 buttons in 6 bytes of input report.”
in fact there are 7 bytes of input report from Byte0 to Byte6