Differences

This shows you the differences between two versions of the page.

--- ctboard:peripherals:button [2016/02/11 07:25] – feur
+++ ctboard:peripherals:button [2022/12/23 11:00] (current) – ruan
@@ Line 1: / Line 1: @@
-====== Button ======
+====== 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 }} Please make sure the CT Board is in the correct mode.
+> {{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**
+> Supported [[ctboard:mode_switch|modes]]: **1**, **2**, **3**, **4**
+\\
 ===== Registers =====
@@ Line 11: / Line 12: @@
 The Registers are read only.
-{{ctboard_button_reg.svg}}
+\\ {{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>
+\\
+<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>
+\\