====== Buttons ======

The 4 buttons on the CT Board are **"active-high"**, e.g. a pressed button is read as logical **"1"**, and debounced. \\
The buttons are accessible over the memory mapped interface or on [[stm32:peripherals:gpio|GPIO port C]]. \\ \\

> {{ctboard:ctboard_mode_1.svg?48px }} {{ctboard:ctboard_mode_2.svg?48px }} {{ctboard:ctboard_mode_3.svg?48px }} {{ctboard:ctboard_mode_4.svg?48px }} Please make sure the CT Board is in the correct mode.
> Supported [[ctboard:mode_switch|modes]]: **1**, **2**, **3**, **4** 
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===== Registers =====

The Registers are read only.

\\ {{ctboard_button_reg.svg}} \\ \\

===== Diagram =====

\\ {{:ctboard:peripherals:ctboard_button.svg?700em}} \\ \\

===== Programming Example =====

The code snippets below show how to use the buttons.

<code c>
#include "reg_ctboard.h"

uint8_t data = CT_BUTTON;                   /* Read all buttons into the lower nibble of a byte. */
</code>
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<code asm>
ADDR_BUTTON     EQU      0x60000210
                
                LDR      r0, =ADDR_BUTTON
                LDRB     r1, [r0, #0]       ; Read all buttons into the lower nibble of a byte.
</code>
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