DAC class

diff --git a/python-lib/usbio.py b/python-lib/usbio.py
index 69ebbea0583fe6565ca5916e21b29996e14500c9..b7eeb402997f53521fbf8e14c5080f2874ab0ba8 100644 (file)
--- a/python-lib/usbio.py
+++ b/python-lib/usbio.py
@@ -523,6 +523,44 @@ class DAC_Channel(object):
     def value(self):
         return self._value
 
+class DAC_word(object):
+    """
+    Container for (easily) constructing an appropriate 32-bit DAC8568 command.
+    """
+    ALL_CHANNELS = 0xf
+
+    def __init__(self):
+        self._word = intbv(0)[32:]
+
+    @property
+    def word(self):
+        return self._word
+
+    #prefix bits are 0xxx always
+    #def prefix(self, value):
+    #    self._word[32:28] = intbv(value, max=2**4)
+
+    def control(self, value):
+        self._word[28:24] = intbv(value, max=2**4)
+
+    def address(self, value):
+        self._word[24:20] = intbv(value, max=2**4)
+
+    def data(self, value):
+        self._word[20:4] = intbv(value, max=2**16)
+
+    def feature(self, value):
+        self._word[4:0] = intbv(value, max=2**4)
+
+    def LDAC(self, bitfield):
+        self.reset()
+        self.control(0x6)
+        self._word[8:0] = intbv(bitfield, max=2**8)
+
+    def reset(self):
+        self._word = intbv(0)[32:]
+
+
 class DAC8568(object):
     CTL_WIDTH = 32
     DAC_WIDTH = 16
@@ -536,6 +574,13 @@ class DAC8568(object):
     def __str__(self):
         return ''.join(map(chr, self.bytes()))
 
+    def updateall(self, value):
+        v = intbv(value, max=self.DAC_WIDTH)
+        d = intbv(0)[32:]
+        d[28:24] = 0x3
+        d[24:20] = 0xf
+        d += (v << 4)
+
     def bytes(self):
         """Return the control data as a byte sequence in MSB..LSB order."""
         w = self.word