Documentation:EVK1100/Joystick
From AVRFreaks Wiki
[edit] Description
The EVK1100 provides a joystick to design Human to Machine Interface for software developments.
Back to the Hardware Reference Page
[edit] Pinout
The joystick inputs are low level active. (ie : the PVR register value is 0 when the joystick is set in a direction and/or pressed, and 1 otherwise)
The pinout is as follow :
| Joystick Pin | Joystick Direction | GPIO Name | Alternate function used |
|---|---|---|---|
| Joy_A | LEFT | PA 25 | SCAN_0 |
| Joy_B | UP | PA 26 | SCAN_1 |
| Joy_C | DOWN | PA 27 | SCAN_2 |
| Joy_D | RIGHT | PA 28 | SCAN_3 |
| EXTINT | PUSH | PA 20 | EXTINT_8 |
see below the hardware schematic :
Back to the Hardware Reference Page
[edit] Using Interrupts
In order to use the joystick, two ways are available :
- Polling on the GPIO Port Value Register
- Using GPIO interrupts to get state changes
Using GPIO interrupts need to :
- Register an interrupt handler for the input (depending on the compiler you are using),
- Set the GPIO control bit for the input,
- Set the GPIO glitch filter bit for the input,
- Configure the GPIO interrupt mask bit for the input to act either on rising edge, falling edge or input change (this mode should be the better for the joystick),
- Set the GPIO interrupt enable bit for the input.
Back to the Hardware Reference Page
