Linux/MSP430F5529: Linux Driver for F5529 for resistive touch panel

Alberto Soattin

Part Number: MSP430F5529
Other Parts Discussed in Thread: AM3352

Tool/software: Linux

Hi,

can we provide a Standard Linux Driver in order to have MSP430F5529 working as MCU controller for Resistive Touch Panel directly recognized by Linux Host (AM3352 or competition)? Important feature is that (differently from HID Mouse) this device need to provide absolute coordinates and not only relatives, because this is a touch panel.

Thanks and regards,

Alberto

over 7 years ago

0 James Evans over 7 years ago

TI__Mastermind 49692 points

Hello Alberto,

Thank you for your post. Instead of using a Resistive Touch Panel, have you considered using our CapTIvate solution for your touch-sensing application?

Getting Started With MSP MCUs With CapTIvate™ Technology

MSP430™ FRAM microcontrollers with CapTIvate™ technology

For questions about the Linux-side drivers on the AM3352, I'd recommend posting them in our Sitara forum. I'm assuming that the Sitara team provides generic Linux drivers that interface with USB HID devices.

On the MSP430 side, we provide several USB HID examples. In our HID H7_Mouse code example in our USB Developers Package, the "dX" and "dY" data are sent in the HID report called "mouseReport". This report is defined as an array with four elements in a structure that correspond to "buttons", "dX", "dY", and "dZ" (see Lines 64 to 71 in 'main.c').

For your application, you can change the report structure and the following portion of code to send over the absolute coordinates read from the touch panel instead.

// Timer has awakened the CPU.  Proceed with main loop...
                if (sendNewMousePosition){
                
                    // Build the report
                    mouseReport.dX =
                        (tableSinCosLookUp[index][0] -
                         tableSinCosLookUp[index - 1][0]) >> 1;
                    mouseReport.dY =
                        (tableSinCosLookUp[index][1] -
                         tableSinCosLookUp[index - 1][1]) >> 1;

                    // Send the report
                    USBHID_sendReport((void *)&mouseReport, HID0_INTFNUM);

                    // Toggle LED on P1.0
                    GPIO_toggleOutputOnPin(LED_PORT, LED_PIN);

                    if (index++ >= 90){
                        index = 1;
                    }
                }
                break;

Here are some additional resources that may be helpful.

Starting a USB Design Using MSP430™ MCUs

4-Wire and 8-Wire Resistive Touch-Screen Controller Using the MSP430™

Using resistive touch screens for human/machine interface

Android Applications With MSP430™ USB on Mobile Devices

USB Keyboard Using MSP430™ Microcontrollers

Regards,

James

MSP Customer Applications