TESTING.md

Testing the Virtual Keyboard at 115200 Baud

Quick Test

1. Terminal 1 - Create the virtual keyboard:

sudo ./virtual_keyboard

You should see:

═══════════════════════════════════════════════════════
  Virtual Keyboard Device Created
═══════════════════════════════════════════════════════
  Device Name    : Virtual Keyboard 115200
  Baudrate       : 115200 bps
  Bit Time       : 8.68 μs
  Char Time      : 86.81 μs
  Vendor ID      : 0x1234
  Product ID     : 0x5678
═══════════════════════════════════════════════════════

2. Terminal 2 - Monitor keyboard events:

# Find the event device number
cat /proc/bus/input/devices | grep -A 5 "Virtual Keyboard 115200"

# Monitor events (replace X with your event number)
sudo evtest /dev/input/eventX

3. Terminal 3 - Write to the keyboard:

sudo ./keyboard_writer
# Type: Hello World
# Press Enter

You should see timing information showing the baudrate-based delays!

Baudrate Verification

The timing should respect the 115200 baud rate:

• Each character takes approximately 86.8 μs to transmit
• Including inter-character delays, expect ~260 μs per character total
• For "Hello World\n" (12 chars): ~3.1 ms total

Performance Test

# Terminal 3
sudo ./keyboard_writer
> ABCDEFGHIJKLMNOPQRSTUVWXYZ
# Watch the timing output to verify baudrate compliance

Testing with Real Applications

Test with evtest

# Monitor the actual events with timestamps
sudo evtest /dev/input/eventX

Test Device Properties

# Check device information
cat /proc/bus/input/devices | grep -A 10 "Virtual Keyboard 115200"

# List all input devices
ls -la /dev/input/by-id/

Advanced: Baudrate Timing Analysis

Create a test file to analyze timing:

# Terminal 3
sudo ./keyboard_writer
> The quick brown fox jumps over the lazy dog

The output will show:

• Number of characters sent
• Baudrate used (115200)
• Total transmission time
• This should align with baudrate calculations