From 0d2d1fc9264a68cbf94444f3444cc5f25402702e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ond=C5=99ej=20Hru=C5=A1ka?= <ondra@ondrovo.com>
Date: Thu, 4 Jan 2018 01:34:03 +0100
Subject: [PATCH] added i2c unit

---
 gex/__init__.py  |  1 +
 gex/units/I2C.py | 72 ++++++++++++++++++++++++++++++++++++++++++++++++
 main.py          | 19 +++++++++++--
 3 files changed, 90 insertions(+), 2 deletions(-)
 create mode 100644 gex/units/I2C.py

diff --git a/gex/__init__.py b/gex/__init__.py
index 526049d..a055cbd 100644
--- a/gex/__init__.py
+++ b/gex/__init__.py
@@ -10,6 +10,7 @@ from gex.Client import Client
 from gex.units.DOut import DOut
 from gex.units.DIn import DIn
 from gex.units.Neopixel import Neopixel
+from gex.units.I2C import I2C
 
 
 # General, low level
diff --git a/gex/units/I2C.py b/gex/units/I2C.py
new file mode 100644
index 0000000..8bd77d2
--- /dev/null
+++ b/gex/units/I2C.py
@@ -0,0 +1,72 @@
+import gex
+
+class I2C(gex.Unit):
+    """
+    I2C master direct access
+    """
+
+    def _type(self):
+        return 'I2C'
+
+    def _begin_i2c_pld(self, address:int, a10bit:bool=False):
+        pb = gex.PayloadBuilder()
+        if a10bit: address |= 0x8000
+        pb.u16(address)
+        return pb
+
+    def write(self, address:int, payload, a10bit:bool=False):
+        """
+        Write to an address
+        """
+        pb = self._begin_i2c_pld(address, a10bit)
+        pb.blob(payload) # payload to write
+        self.query(0x80, pb.close())
+
+    def read(self, address:int, count, a10bit:bool=False):
+        """
+        Read from an address
+        """
+        pb = self._begin_i2c_pld(address, a10bit)
+        pb.u16(count) # number of bytes to read
+        self.query(0x01, pb.close())
+
+    def read_reg(self, address:int, reg, width:int=1, a10bit:bool=False, endian='little'):
+        """
+        Read a single register
+        """
+        return self.read_regs(address, reg, count=1, width=width, a10bit=a10bit, endian=endian)[0]
+
+    def read_regs(self, address:int, reg, count:int, width:int=1, a10bit:bool=False, endian='little'):
+        """
+        Read multiple registers from an address
+        """
+        pb = self._begin_i2c_pld(address, a10bit)
+        pb.u8(reg)
+        pb.u8(width*count) # we assume the device will auto-increment (most do)
+        resp = self.query(0x03, pb.close())
+
+        fields = []
+        pp = gex.PayloadParser(resp.data, endian=endian)
+        for i in range(0, count):
+            if width==1: fields.append(pp.u8())
+            elif width==2: fields.append(pp.u16())
+            elif width==3: fields.append(pp.u24())
+            elif width==4: fields.append(pp.u32())
+            else: raise Exception("Bad width")
+        return fields
+
+    def write_reg(self, address:int, reg, value:int, width:int=1, a10bit:bool=False, endian='little'):
+        """
+        Write a to a single register
+        """
+        pb = self._begin_i2c_pld(address, a10bit)
+        pb.u8(reg)
+
+        pb.endian = endian
+        if width == 1: pb.u8(value)
+        elif width == 2: pb.u16(value)
+        elif width == 3: pb.u24(value)
+        elif width == 4: pb.u32(value)
+        else: raise Exception("Bad width")
+
+        self.query(0x82, pb.close())
diff --git a/main.py b/main.py
index ebef22b..f7d6a4b 100644
--- a/main.py
+++ b/main.py
@@ -50,14 +50,29 @@ if False:
         strip.write((b << 2) | ((~b) & 1))
         time.sleep(.02)
 
-if True:
+if False:
     neo = gex.Neopixel(client, 'npx')
 
     print('We have %d neopixels.\n' % neo.get_len())
 
+    #neo.load([0xF0F0F0,0,0,0xFF0000])
+
     # generate a little animation...
     for i in range(0,512):
         j = i if i < 256 else 255-(i-256)
         neo.load([0x660000+j, 0x3300FF-j, 0xFFFF00-(j<<8), 0x0000FF+(j<<8)-j])
-        time.sleep(.005)
+        time.sleep(.001)
+
+    neo.load([0,0,0,0])
+
+
+i2c = gex.I2C(client, 'i2c')
+
+# i2c.write(0x76, payload=[0xD0])
+# print(i2c.read(0x76, count=1))
+
+print(i2c.read_reg(0x76, 0xD0))
+print("%x" % i2c.read_reg(0x76, 0xF9, width=3, endian='big'))
 
+i2c.write_reg(0x76, 0xF4, 0xFA)
+print(i2c.read_reg(0x76, 0xF4))