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The following commit(s) were added to refs/heads/master by this push:
new 117947b drivers/led/ws2812: fix comments
117947b is described below
commit 117947b5a1a3b19e20549f48055180d5f018b0ce
Author: Diego Herranz <diegoherr...@diegoherranz.com>
AuthorDate: Wed Dec 2 21:21:36 2020 +0000
drivers/led/ws2812: fix comments
Complete or improve some explanations and fix some typos
---
drivers/leds/ws2812.c | 18 +++++++++---------
1 file changed, 9 insertions(+), 9 deletions(-)
diff --git a/drivers/leds/ws2812.c b/drivers/leds/ws2812.c
index 0a5ca85..efa8a77 100644
--- a/drivers/leds/ws2812.c
+++ b/drivers/leds/ws2812.c
@@ -39,16 +39,16 @@
* Pre-processor Definitions
****************************************************************************/
-/* These are the tuning parameters to meeting timeing requirements */
+/* These are the tuning parameters to meet timing requirements */
#if CONFIG_WS2812_FREQUENCY == 4000000
-# define WS2812_RST_CYCLES 30 /* 60us (>50us)*/
+# define WS2812_RST_CYCLES 30 /* 60us (>50us) */
# define WS2812_ZERO_BYTE 0b01000000 /* 250 ns (200ns - 500ns) */
# define WS2812_ONE_BYTE 0b01110000 /* 750 ns (550ns - 850ns) */
#elif CONFIG_WS2812_FREQUENCY == 8000000
-# define WS2812_RST_CYCLES 60 /* 60us (>50us)*/
+# define WS2812_RST_CYCLES 60 /* 60us (>50us) */
# define WS2812_ZERO_BYTE 0b01100000 /* 250 ns (200ns - 500ns) */
-# define WS2812_ONE_BYTE 0b01111100 /* 750 ns (550ns - 850ns) */
+# define WS2812_ONE_BYTE 0b01111100 /* 625 ns (550ns - 850ns) */
#else
# error "Unsupported SPI Frequency"
#endif
@@ -60,11 +60,11 @@
* [<----reset bytes---->|<-RGBn->...<-RGB0->|<----reset bytes---->]
*
* It is important that this is shipped as close to one chunk as possible
- * in order to meet timeing requirements and to keep MOSI from going high
+ * in order to meet timing requirements and to keep MOSI from going high
* between transactions. Some chips will leave MOSI at the state of the
* MSB of the last byte for this reason it is recommended to shift the
- * bytes that represents the zero and one so that the MSB is 1. The reset
- * clocks will pad the shortend low at the end.
+ * bits that represents the zero or one waveform so that the MSB is 0.
+ * The reset clocks will pad the shortened low at the end.
*/
#define TXBUFF_SIZE(n) (WS2812_RST_CYCLES * 2 + n * WS2812_BYTES_PER_LED)
@@ -250,7 +250,7 @@ static ssize_t ws2812_write(FAR struct file *filep, FAR
const char *buffer,
return -1;
}
- /* We need at least one display, so 1 byte */
+ /* We need at least one LED, so 1 byte */
if (buflen < 1)
{
@@ -309,7 +309,7 @@ static ssize_t ws2812_write(FAR struct file *filep, FAR
const char *buffer,
* Description:
* This routine is called when seeking the WS2812 device. This can be used
* to address the starting LED to write. This should be done on a full
- * color boundary which is 32bits. e.g. LED0 - offset 0 LED 8.
+ * color boundary which is 32bits. e.g. LED0 - offset 0, LED 8 - offset 32
*
****************************************************************************/
