X-Git-Url: https://defiant.homedns.org/gitweb/?a=blobdiff_plain;f=bus_pirate.py;h=cdd259fa7581ee42dba23da879fbf10b3aa4d287;hb=c9dbcc66879f0e1d8beb05b49179fcb200ef8cf0;hp=a148f1a67f16b4a0251bc1ed704750d5d3929088;hpb=8fb99f53115a9e9294e6289d4c1f7ec9bc7f81a7;p=pyshared.git diff --git a/bus_pirate.py b/bus_pirate.py index a148f1a..cdd259f 100644 --- a/bus_pirate.py +++ b/bus_pirate.py @@ -64,6 +64,29 @@ class BP: v = struct.unpack(">h", s) return v[0]/1024.0*6.6 + # http://codepad.org/qtYpZmIF + def pwm(self, freq, duty_cycle_percent): + lPrescaler = {0:1, 1:8 , 2:64, 3:256} + Fosc = 32e6 + Tcy = 2.0 / Fosc + period = 1.0 / freq + prescaler = 1 + + # find needed prescaler + for i in range(4): + prescaler = lPrescaler[i] + PRy = period * 1.0 / (Tcy * prescaler) + PRy = int(PRy - 1) + OCR = int(PRy * duty_cycle_percent) + + if PRy < (2 ** 16 - 1): + break # valid value for PRy, keep values + + cmd = struct.pack(">BBHH", 0b00010010, i, OCR, PRy) + ret = self.command(cmd, 1) + if ord(ret) != 0x1: + raise Exception() + def spi_command(self, cmd): ret = self.command(cmd, 1) if ord(ret) != 0x1: @@ -107,12 +130,19 @@ class BP: state = self.update_io() return state & (1 << dPinToBit[pin]) - def mode_i2c(self, bEnablePower=False, bEnablePullup=False): + def mode_i2c(self, bEnablePower=False, bEnablePullup=False, iSpeedkHz=100): if self.command(chr(0x2), 4) != "I2C1": raise Exception() - # 100kHz - ret = self.command(chr(0b01100010), 1) + dSpeeds = { + 5: 0x0, + 50: 0x1, + 100: 0x2, + 400: 0x3, + } + if iSpeedkHz not in dSpeeds.keys(): + raise Exception("Invalid I2C speed") + ret = self.command(chr(0b01100000 | dSpeeds[iSpeedkHz]), 1) if ord(ret) != 0x1: raise Exception() @@ -128,7 +158,7 @@ class BP: def i2c_write(self, addr, reg, s): # 1. Write # command (1) | number of write bytes (2) | number of read bytes (2) | bytes to write (0..) - msg = struct.pack(">BHHBB%ds" % len(s), 0x08, 2+len(s), 0, addr<<1, reg, s) + msg = struct.pack(">BHHBB%ds" % len(s), 0x08, 2+len(s), 0, addr, reg, s) ret = self.command(msg, 1) if ord(ret[0]) != 0x1: @@ -139,7 +169,7 @@ class BP: self.i2c_write(addr, reg, "") # command (1) | number of write bytes (2) | number of read bytes (2) | bytes to write (0..) - msg = struct.pack(">BHHB", 0x08, 1, 1+num_read, (addr<<1) | 0x1) + msg = struct.pack(">BHHB", 0x08, 1, num_read, addr | 0x1) ret = self.command(msg, 1 + num_read) if ord(ret[0]) != 0x1: @@ -149,7 +179,7 @@ class BP: def i2c_search(self): for i in range(128): - msg = struct.pack(">BHHB", 0x08, 1, 1, i<<1) + msg = struct.pack(">BHHB", 0x08, 1, 1, i) ret = self.command(msg, 1) if ord(ret) == 0x1: print "Found I2C Addr: 0x%x" % (i & ~0x1)