Driver for '595 shift register

tasmota/berry/drivers/Shift595.be

@@ -0,0 +1,80 @@
+# Sample Relay driver for 595 shift registers
+# -------------------------------------------------------------------------
+# You can cascade multiple '595 for a total of 28 relays (including other native relays)
+# Include the following lines in 'preinit.be'
+#   import Shift595
+#   tasmota.add_driver(Shift595(srclk,ser,rclk,count,inverted))
+# where
+#   srclk     : GPIO number connected to the 595's SRCLK pin (serial shift clock)
+#   ser       : GPIO number connected to the 595's SER pin (serial data in)
+#   rclk      : GPIO number connected to the 595's RCLK pin (transfer to output)
+#   count     : number of used output pins / relays (must be consecutive)
+#   inverted  : if true, relay is driven by a 0/LOW inverted (instead of 1/HIGH)
+#
+# To use multiple '595, connects
+#   all SRCLK together to GPIO srclk
+#   all RCLK together to GPIO rclk
+#   GPIO ser to SER input of first '595
+#   QH' output of first '595 to SER input of 2nd '595 and so on
+# -------------------------------------------------------------------------
+
+import string
+import gpio
+
+class Shift595
+
+  var srclk, ser, rclk, count, inverted
+  var first, state
+
+  def log_relay(relay)
+    var s = ""
+    for r:relay if r s+='1' else s+='0' end end
+    log("595: "+s,2)
+  end
+
+  def shift_out(relay)
+    self.log_relay(relay)
+
+    for i:0..size(relay)-1
+      var bit
+      bit = (relay[size(relay)-1 - i]) ? int(!self.inverted) : int(self.inverted)
+      gpio.digital_write(self.srclk, 0)
+      gpio.digital_write(self.ser, bit)
+      gpio.digital_write(self.srclk, 1)
+    end
+
+    gpio.digital_write(self.rclk, 1)
+    gpio.digital_write(self.rclk, 0)
+    gpio.digital_write(self.srclk, 0)
+  end
+
+  def init(srclk, ser, rclk, count, inverted)
+    self.srclk= srclk
+    self.ser = ser
+    self.rclk = rclk
+    self.count = count
+    self.inverted = inverted
+    self.first = tasmota.global.devices_present
+    tasmota.global.devices_present += count
+
+    gpio.pin_mode(self.srclk, gpio.OUTPUT)
+    gpio.pin_mode(self.ser,    gpio.OUTPUT)
+    gpio.pin_mode(self.rclk,   gpio.OUTPUT)
+    gpio.digital_write(self.srclk, 0)
+    gpio.digital_write(self.ser,    0)
+    gpio.digital_write(self.rclk,   0)
+
+    self.state = 0
+  end
+
+  def set_power_handler(cmd, idx)
+    var new_state = tasmota.get_power()[self.first..self.first+self.count]
+    if self.state != new_state
+      self.state = new_state
+      self.shift_out(self.state)
+    end
+  end
+
+end
+
+return Shift595 # allow using 'import' instead of 'load()'