Touchpanel Driver Development

The goal of this lab is to develop a hardware driver to interface the resistive touch panel with the STM32 microcontroller. The final product is touchDriver.py.

(Source: https://bitbucket.org/dhmorse/me-405/src/master/Lab07/)

Hardware Setup

I disassebled the platform from the body of the machine to make it easier to work with the board and table simultaneously. Beginning this project I made a soldering mistake. After desoldering the FPC adapter from the main assembly the through holes were blocked. Despite spending hours attempting to remove the blocking solder and eventully recruiting a CPE friend for assistance I was unsuccessful and fried the board (a new one is coming in the mail). Thankfully, a classmate was generous enough to let me borrow his! The following is my set-up for testing and results from calibration:

RTP Testing Set-up

Results:

Calibration yeilded the following results: Bottom Left : (0380, 3800) Bottom Right: (3600, 3800) Top Left : (0420, 0220) Top Right: (3620, 0220) Center: (2020, 2020)

RTP Calibration Results

During testing x-scan and y-scan speeds were measuered to be 300us +/- 5. Total scan time took less than 1000us at roughly 975us for x, y, and z scanning. Scan times were measured using utime.ticks_us with extraneous print statements commented out. See below for output results:

RTP Scan Time Results

Results are formated: [xscan result] [yscan result] [zscan result] [total op. time].

Author: Hunter Morse

Date: Winter 2021