Differences

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--- stm32:peripherals:gpio_input [2016/02/25 07:11] – feur
+++ stm32:peripherals:gpio_input [2022/12/28 08:15] (current) – ruan
@@ Line 1: / Line 1: @@
 ====== General Purpose Input ======
   * The output buffer is disabled.
   * The Schmitt trigger input is active.
-  * The pull-up and -down resistors are active, according to [[gpio#registers|PUPDR]].
+  * The pull-up and -down resistors are active, according to [[#PUPDR|PUPDR]].
   * Input data is sampled every AHB clock.
   * Input data register holds I/O state.
@@ Line 11: / Line 9: @@
 \\ {{gpio_input.svg}} \\ \\
-==== Configuration Registers ====
+===== Programming Instructions =====
+==== Enable Peripheral ====
+Make sure the peripheral is enabled:
+  * Enable GPIOx in ''RCC->AHBENR[0]''.
+==== Setup input mode ====
+Configure the MODE and PUPDR register, for every pin that should act as digital input:
+  * Write ''0x00'' to the corresponding fields in ''GPIOx->MODE''.
+  * Configure pull-up / -down in ''GPIOx->PUPDR''.
+\\
+===== Configuration Registers =====
+==== GPIOx_MODER - GPIO port mode register ====
+\\ {{gpio_reg_common.svg}} \\ \\
+|< 100% 5em 5em >|
+|Pin x|00|Input mode (reset state)|
+==== GPIOx_PUPDR - GPIO port pull-up / pull-down register ====
+\\ {{gpio_reg_common.svg}} \\ \\
+|< 100% 5em 5em >|
+|Pin x|00|No pull-up, pull-down (reset state)|
+|:::|01|Pull-up|
+|:::|10|Pull-down|
-|< 100% 10em >|
+===== Data Registers =====
-|[[gpio#registers|MODER]]|Select input mode|
-|[[gpio#registers|PUPDR]]|Select pull-up / -down configuration|
-==== Data Registers ====
+==== GPIOx_IDR - Port input data register ====
-|< 100% 10em >|
+\\ {{gpio_reg_idr.svg}} \\ \\
-|[[gpio#registers|IDR]]|Holds pin state|
-===== Legend =====
+* Register is read only \\ \\
-\\ {{legende.svg}} \\ \\