From ec7bc3665993ee4747844de7dc3cb1bd42a75c42 Mon Sep 17 00:00:00 2001
From: Phil Howard <phil@pimoroni.com>
Date: Thu, 21 Jul 2022 14:11:26 +0100
Subject: [PATCH] MicroPython: Add ShiftRegister class.

---
 micropython/modules_py/pimoroni.py | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/micropython/modules_py/pimoroni.py b/micropython/modules_py/pimoroni.py
index 8c8504f8..40adec99 100644
--- a/micropython/modules_py/pimoroni.py
+++ b/micropython/modules_py/pimoroni.py
@@ -196,3 +196,31 @@ class Buzzer:
         self.pwm.freq(freq)
         self.pwm.duty_u16(int(65535 * duty))
         return True
+
+
+class ShiftRegister:
+    def __init__(self, clk, lat, dat):
+        self.clk = Pin(clk, Pin.OUT)
+        self.lat = Pin(lat, Pin.OUT)
+        self.dat = Pin(dat, Pin.IN)
+
+    def __iter__(self):
+        self.lat.off()
+        self.lat.on()
+        for _ in range(8):
+            yield self.dat.value()
+            self.clk.on()
+            self.clk.off()
+
+    def __getitem__(self, k):
+        return list(self)[k]
+
+    def read(self):
+        out = 0
+        for bit in self:
+            out <<= 1
+            out += bit
+        return out
+
+    def is_set(self, mask):
+        return self.read() & mask == mask