diff --git a/lib/led_ws2812b.c b/lib/led_ws2812b.c
index 12735ee..8b0c904 100644
--- a/lib/led_ws2812b.c
+++ b/lib/led_ws2812b.c
@@ -37,14 +37,14 @@
 #define WS2812B_SPI_DR SPI1_DR
 #define WS2812B_SPI_RCC RCC_SPI1
 #define WS2812B_SPI_PORT GPIOA
-#define WS2812B_SPI_CLK GPIO_SPI1_SCK
-#define WS2812B_SPI_DOUT GPIO_SPI1_MISO 
+#define WS2812B_SPI_CLK GPIO_SPI1_SCK // connect PWM output to clock input on PA5
+#define WS2812B_SPI_DOUT GPIO_SPI1_MISO // connect WS2812b DIN to MISO pin PA6
 #define WS2812B_TIMER TIM3
 #define WS2812B_TIMER_RCC RCC_TIM3
 #define WS2812B_TIMER_OC TIM_OC3
 #define WS2812B_CLK_RCC RCC_GPIOB
 #define WS2812B_CLK_PORT GPIOB
-#define WS2812B_CLK_PIN GPIO_TIM3_CH3
+#define WS2812B_CLK_PIN GPIO_TIM3_CH3 // connect SPI clock input to PWM clock output PB0
 #define WS2812B_DMA DMA1 // DMA1 supports SPI1_TX interrupt
 #define WS2812B_DMA_RCC RCC_DMA1 // follows previous definition
 #define WS2812B_DMA_CH DMA_CHANNEL3 // only DMA1 channel 3 supports SPI1_TX interrupt