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authorAndreas Bogk <andreas@oxytocin.(none)>2009-01-17 13:14:19 +0100
committerAndreas Bogk <andreas@oxytocin.(none)>2009-01-17 13:14:19 +0100
commitd2ba68881c57d9efb978ba2454f989733b37cb15 (patch)
tree6eb4d498fffc4e8bad0eaba03429304ab1ef31a9
parentcd41bd8ced5e11f2202221aadee725d2c6137d29 (diff)
A5 implementation in MyHDL.
-rw-r--r--A5.1/MyHDL/A5.py127
1 files changed, 127 insertions, 0 deletions
diff --git a/A5.1/MyHDL/A5.py b/A5.1/MyHDL/A5.py
new file mode 100644
index 0000000..6530357
--- /dev/null
+++ b/A5.1/MyHDL/A5.py
@@ -0,0 +1,127 @@
+from myhdl import *
+
+def Lfsr(clk, reset, enable, reg, taps):
+
+ @always(clk.posedge)
+ def shiftRegister():
+ if enable:
+ output = 0
+
+ for tap in taps:
+ output ^= reg[tap]
+
+ reg.next = ((reg << 1) + (output & 1)) % reg.max
+
+ return shiftRegister
+
+def printLfsr(clk, reg):
+
+ @always(clk.negedge)
+ def doPrint():
+ print "LFSR value %s" % bin(reg, len(reg))
+
+ return doPrint
+
+def ClkDriver(clk, period=20):
+
+ lowTime = int(period/2)
+ highTime = period - lowTime
+
+ @instance
+ def driveClk():
+ while True:
+ yield delay(lowTime)
+ clk.next = 1
+ yield delay(highTime)
+ clk.next = 0
+
+ return driveClk
+
+def ResetGen(reset, time):
+ @instance
+ def driveReset():
+ reset.next = 0
+ yield delay(time)
+ reset.next = 1
+
+ return driveReset
+
+def Lfsr_tb():
+ clk = Signal(0)
+ reset = Signal(0)
+ oscillator = ClkDriver(clk)
+ reg = Signal(intbv(23)[19:])
+ lfsr = Lfsr(clk, reg, [13, 16, 17, 18], reset)
+ printer = printLfsr(clk, reg)
+ return instances()
+
+def muxReg(clk, reset, reg, R1, R2, R3):
+ return loadReg
+
+def a5(clk, reset, reg):
+
+ R1 = Signal(intbv(0)[19:])
+ R2 = Signal(intbv(0)[22:])
+ R3 = Signal(intbv(0)[23:])
+
+ en1 = Signal(intbv(1)[1:])
+ en2 = Signal(intbv(1)[1:])
+ en3 = Signal(intbv(1)[1:])
+
+ @always(clk.posedge, reset.negedge)
+ def loadReg():
+ if reset == 0:
+ print "Reset"
+ R1.next = reg[64:45]
+ R2.next = reg[45:23]
+ R3.next = reg[23:0]
+ else:
+ reg.next[64:45] = R1
+ reg.next[45:23] = R2
+ reg.next[23:0] = R3
+
+ lfsr1 = Lfsr(clk, reset, en1, R1, [13, 16, 17, 18])
+ lfsr2 = Lfsr(clk, reset, en2, R2, [20, 21])
+ lfsr3 = Lfsr(clk, reset, en3, R3, [7, 20, 21, 22])
+
+ @always_comb
+ def clock():
+ if R1[8] + R2[10] + R3[10] > 2:
+ en1.next = R1[8]
+ en2.next = R2[10]
+ en3.next = R3[10]
+ else:
+ en1.next = not R1[8]
+ en2.next = not R2[10]
+ en3.next = not R3[10]
+
+
+ return instances()
+
+def a5_tb():
+ clk = Signal(intbv(0)[1:])
+ reset = Signal(intbv(0)[1:])
+ oscillator = ClkDriver(clk)
+ resetgen = ResetGen(reset, 35)
+ reg = Signal(intbv(0xdeadbeefcafebabe)[64:])
+ lfsr = a5(clk, reset, reg)
+ printer = printLfsr(clk, reg)
+ return instances()
+
+
+
+
+
+def sayhello():
+ clk = Signal(0)
+
+ oscillator = ClkDriver(clk)
+
+ hello = Hello(clk)
+
+ return instances()
+
+#inst = a5_tb()
+#sim = Simulation(inst)
+#sim.run()
+a5_inst = toVHDL(a5_tb)
personal git repositories of Harald Welte. Your mileage may vary