added initial bus pirate class

diff --git a/bus_pirate.py b/bus_pirate.py
new file mode 100644 (file)
index 0000000..edc5699
--- /dev/null
+++ b/bus_pirate.py
@@ -0,0 +1,71 @@
+#!/usr/bin/env python
+# -*- coding: iso-8859-15 -*-
+
+import serial
+import struct
+
+
+# http://dangerousprototypes.com/docs/Bitbang
+# http://dangerousprototypes.com/docs/SPI_(binary)
+class BP:
+       def __init__(self, sDevice):
+               self.pSerial = serial.Serial(sDevice, baudrate=115200, timeout=0.1)
+               self.mode_bit_bang()
+
+       def command(self, cmd, num_read):
+               self.pSerial.write(cmd)
+               return self.pSerial.read(num_read)
+
+       def mode_bit_bang(self):
+               for i in range(20):
+                       if self.command(chr(0x0), 5) == "BBIO1":
+                               return
+               raise Exception()
+
+       def mode_spi(self, mode, speed):
+               if self.command(chr(0x1), 4) != "SPI1":
+                       raise Exception()
+               self.spi_set_mode(mode)
+               self.spi_set_speed(speed)
+
+       def spi_set_mode(self, mode):
+               if mode not in range(0, 4):
+                       raise Exception("Unknown mode")
+               if mode == 0:
+                       self.spi_command(chr(0b10001000))
+               elif mode == 1:
+                       self.spi_command(chr(0b10001010))
+               elif mode == 2:
+                       self.spi_command(chr(0b10001100))
+               elif mode == 3:
+                       self.spi_command(chr(0b10001110))
+
+
+       def spi_set_speed(self, speed):
+               lSpeeds = ["30kHz", "125kHz", "250kHz", "1MHz", "2MHz", "2.6MHz", "4MHz", "8MHz"]
+               val = lSpeeds.index(speed)
+               self.spi_command(chr(0b01100000 | val))
+
+       def command_byte_set(self, bit):
+               enable = 1<<bit
+               state = ord(self.command(chr(0x80 | enable, 1)))
+               if not state & enable:
+                       raise Exception("Got 0x%x, expected 0xc0" % state)
+
+       def power_enable(self):
+               self.command_byte_set(6)
+       
+       def get_adc(self):
+               s = self.command(chr(0x14), 2)
+               v = struct.unpack(">h", s)
+               return v[0]/1024.0*6.6
+
+       def spi_command(self, cmd):
+               ret = self.command(cmd, 1)
+               if ord(ret) != 0x1:
+                       raise Exception()
+       
+       def spi_write(self, data, num_read=0):
+               if len(data) > 4096:
+                       raise Exception("SPI Data String too long")
+               return self.spi_command(struct.pack(">Bhh%ds" % len(data), 0x04, len(data), num_read, data))