From c6b07ae2f7cb8664981d5cf9c2a52713ff3565f9 Mon Sep 17 00:00:00 2001
From: "Phani Pavan K: iDellToast" <kphanipavan@gmail.com>
Date: Sat, 23 Nov 2024 12:15:49 +0530
Subject: [PATCH] add binary counter example

---
 1_Basic_GPIO/digitalOut.md | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/1_Basic_GPIO/digitalOut.md b/1_Basic_GPIO/digitalOut.md
index dc2c9c8..eb9aec4 100644
--- a/1_Basic_GPIO/digitalOut.md
+++ b/1_Basic_GPIO/digitalOut.md
@@ -224,3 +224,25 @@ Code to turn the fan on and off with a 2 second delay:
 }
 
 ```
+
+## Binary LED Counter
+
+This example uses 5 LEDS to visualize a 5 bit binary counter. Mask commands are used to set the LEDS simultaneously.
+
+```c
+int pinMask = 0b1111100000000000;
+int dirMask = 0b1111100000000000;
+int counter = 0;
+gpio_init_mask(pinMask);
+gpio_set_dir_masked(pinMask, dirMask);
+while (true)
+{
+    gpio_put_masked(pinMask, counter<<11);
+    counter++;
+    sleep_ms(500);
+}
+```
+
+`gpio_put_masked` has similar characteristics as other masked functions. This will set the output pins according to the second argument simultaneously, `counter<<11` in this case. Counter is left shifted by 11 bits to align with the mask.
+
+if counter is `11001`, `counter<<11` will be `1100100000000000`.