synth.py

from wishbonedevice import WishBoneDevice
import fractions as _frac
import logging
import time

logging.getLogger(__name__).addHandler(logging.NullHandler())

class LMX2581(WishBoneDevice):
	""" LMX2581 Frequency Synthesizer """

	DICTS = [
	#00
		{
		'ID' : 1 << 31,
		'FRAC_DITHER' : 0b11 << 29,
		'NO_FCAL' : 1 << 28,
		'PLL_N' : 0b111111111111 << 16, # PLL[11:0] PLL Feedback Divider Value
		'PLL_NUM_L' : 0b111111111111 << 4, # PLL_NUM[11:0] PLL Fractional Numerator
		},
	#01
		{
		'CPG' : 0b11111 << 27,
		'VCO_SEL' : 0b11 << 25,
		'PLL_NUM_H' : 0b1111111111 << 15, # PLL_NUM[21:12] PLL Fractional Numerator
		'FRAC_ORDER' : 0b111 << 12,
		'PLL_R' : 0b11111111 << 4, # PLL_R[7:0] divides the OSCin frequency
		},
	#02
		{
		'OSC_2X' : 1 << 29,
		'CPP' : 1 << 27,
		'PLL_DEN' : 0b1111111111111111111111 << 4, # PLL_DEN[21:0] PLL Fractional Denominator
		},
	#03
		{
		'VCO_DIV' : 0b11111 << 18, # VCO_DIV[4:0] VCO Divider Value
		'OUTB_PWR' : 0b111111 << 12,
		'OUTA_PWR' : 0b111111 << 6,
		'OUTB_PD' : 1 << 5,
		'OUTA_PD' : 1 << 4,
		},
	#04
		{
		'PFD_DLY' : 0b111 << 29,
		'FL_FRCE' : 1 << 28,
		'FL_TOC' : 0b111111111111 << 16,
		'FL_CPG' : 0b11111 << 11,
		'CPG_BLEED' : 0b111111 << 4,
		},
	#05
		{
		'OUT_LDEN' : 1 << 24,
		'OSC_FREQ' : 0b111 << 21,
		'BUFEN_DIS' : 1 << 20,
		'VCO_SEL_MODE' : 0b11 << 15,
		'OUTB_MUX' : 0b11 << 13,
		'OUTA_MUX' : 0b11 << 11,
		'0_DLY' : 1 << 10,
		'MODE' : 0b11 << 8,
		'PWDN_MODE' : 0b111 << 5,
		'RESET' : 1 << 4,
		},
	#06
		{
		'RD_DIAGNOSATICS' : 0b11111111111111111111 << 11,
		'RDADDR' : 0b1111 << 5,
		'UWIRE_LOCK' : 1 << 4,
		},
	#07
		{
		'FL_SELECT' : 0b11111 << 26,
		'FL_PINMODE' : 0b111 << 23,
		'FL_INV' : 1 << 22,
		'MUXOUT_SELECT' : 0b11111 << 17,
		'MUX_INV' : 1 << 16,
		'MUXOUT_PINMODE' : 0b111 << 13,
		'LD_SELECT' : 0b11111 << 8,
		'LD_INV' : 1 << 7,
		'LD_PINMODE' : 0b111 << 4,
		},
	#08
		None,
	#09
		None,
	#10
		None,
	#11
		None,
	#12
		None,
	#13
		{
		'DLD_ERR_CNT' : 0b1111 << 28,
		'DLD_PASS_CNT' : 0b1111111111 << 18,
		'DLD_TOL' : 0b111 << 15,
		},
	#14
		None,
	#15
		{
		'VCO_CAP_MAN' : 1 << 12,
		'VCO_CAPCODE' : 0b11111111 << 4,
		},
	]

	MASK_DIAG = {
		'VCO_SELECT': 0b11 << 18+11,
		'FIN_DETECT': 0b1 << 17+11,
		'OSCIN_DETECT': 0b1 << 16+11,
		'VCO_DETECT': 0b1 << 15+11,
		'CAL_RUNNING': 0b1 << 10+11,
		'VCO_RAIL_HIGH': 0b1 << 9+11,
		'VCO_RAIL_LOW': 0b1 << 8+11,
		'VCO_TUNE_HIGH': 0b1 << 6+11,
		'VCO_TUNE_VALID': 0b1 << 5+11,
		'FLOUT_ON': 0b1 << 4+11,
		'DLD': 0b1 << 3+11,
		'LD_PINSTATE': 0b1 << 2+11,
		'CE_PINSTATE': 0b1 << 1+11,
		'BUFEN_PINSTATE': 0b1 << 0+11
	}

	CMD10 = 0b00100001000000000101000011001010 # Not disclosed to user
	CMD09 = 0b00000011110001111100000000111001 # Not disclosed to user
	CMD08 = 0b00100000011111011101101111111000 # Not disclosed to user
	

	# Using recommanded parameter settings in the following datasheet
	# http://www.ti.com/lit/ds/symlink/lmx2581.pdf
	# Also borrow some lines from https://github.com/domagalski/snap-synth

	def __init__(self, interface, controller_name, fosc=10):
		super(LMX2581, self).__init__(interface, controller_name) 
		# A non-None address list
		self.A_DICT_LIST = [self.DICTS.index(a) for a in self.DICTS if a != None]
		self.FOSC = fosc 		# 10 MHz from GPS module
		self.freq_pd = self.FOSC / 1

	def init(self):

		# Generated via TI http://www.ti.com/tool/clockdesigntool
		# and via TI http://www.ti.com/tool/codeloader
		r05=0x40870015
		r15=0x021FE80F
		r13=0x4082C10D
		r10=0x210050CA
		r09=0x03C7C039
		r08=0x207DDBF8
		r07=0x00082317
		r06=0x000004C6
		r05=0x0010A805
		r04=0x00000004
		r03=0x2004F3C3
		r02=0x0C000642
		r01=0xD0000011
		r00=0x60C80000

		self.reset()
		self.write(r15)
		self.write(r13)
		self.write(r10)
		self.write(r09)
		self.write(r08)
		self.write(r07)
		self.write(r06)
		self.write(r05)
		self.write(r04)
		self.write(r03)
		self.write(r02)
		self.write(r01)
		self.write(r00)

		time.sleep(0.02)

		self.write(r00)

	def powerOn(self):
		self.setWord(0, "PWDN_MODE")

	def powerOff(self):
		self.setWord(1, "PWDN_MODE")

	def outputPower(self,p=15):
		self.setWord(p, "OUTA_PWR")
		self.setWord(p, "OUTB_PWR")

	def get_osc_values(self, synth_mhz, ref_signal):
		""" This function gets oscillator values
		"""
		# Equation for the output frequency.
		# f_out = f_osc * OSC_2X / PLL_R * (PLL_N + PLL_NUM/PLL_DEN) / VCO_DIV
		# XXX Right now, I'm not going to use OSC_2X or PLL_R, so this becomes
		# f_out = f_osc * (PLL_N + PLL_NUM/PLL_DEN) / VCO_DIV
		
		# Get a good VCO_DIV. The minimum VCO frequency is 1800.
		# Though the min frequency is 1800, but mostly LMX2581 doesn't get
		# locked at this frequency. Change 1800 to 1900
		vco_min = 1900; vco_max = 3800
		if synth_mhz > vco_min and synth_mhz < vco_max:
			# Bypass VCO_DIV by properly setting OUTA_MUX and OUTB_MUX
			VCO_DIV = None
		else:
			vco_guess = int(vco_min / synth_mhz) + 1
			VCO_DIV = vco_guess + vco_guess%2
		
		# Get PLLN, PLL_NUM, and PLL_DEN
		pll = float(1 if VCO_DIV is None else VCO_DIV) * synth_mhz / ref_signal
		PLL_N = int(pll)
		frac = pll - PLL_N
		if frac < 1.0/(1<<22): # smallest fraction on the synth
			PLL_NUM = 0
			PLL_DEN = 100
		else:
			fraction = _frac.Fraction(frac).limit_denominator(1<<22)
			PLL_NUM = fraction.numerator
			PLL_DEN = fraction.denominator

		return (PLL_N, PLL_NUM, PLL_DEN, VCO_DIV)

	def setFreq(self, synth_mhz):

		self.setWord(1, 'NO_FCAL')

		PLL_N, PLL_NUM, PLL_DEN, VCO_DIV = self.get_osc_values(synth_mhz,self.FOSC)

		# Select the VCO frequency
		# VCO1: 1800 to 2270 NHz
		# VCO2: 2135 to 2720 MHz
		# VCO3: 2610 to 3220 MHz
		# VCO4: 3075 to 3800 MHz
		freq_vco = self.freq_pd * (PLL_N + float(PLL_NUM)/PLL_DEN)
		if freq_vco >= 1800 and freq_vco <= 2270:
			VCO_SEL = 0
		elif freq_vco >= 2135 and freq_vco <= 2720:
			VCO_SEL = 1
		elif freq_vco >= 2610 and freq_vco <= 3220:
			VCO_SEL = 2
		elif freq_vco >= 3075 and freq_vco <= 3800:
			VCO_SEL = 3
		else:
			raise ValueError('VCO frequency is out of range.')
		self.setWord(VCO_SEL, 'VCO_SEL')

		# Dithering is set in R0, but it is needed for R1 stuff.
		if PLL_NUM and PLL_DEN > 200 and not PLL_DEN % 2 and not PLL_DEN % 3:
			FRAC_DITHER = 2
		else:
			FRAC_DITHER = 3
		self.setWord(FRAC_DITHER, 'FRAC_DITHER')
			
		# Get the Fractional modulator order
		if not PLL_NUM:
			FRAC_ORDER = 0
		elif PLL_DEN < 20:
			FRAC_ORDER = 1
		elif PLL_DEN % 3 and FRAC_DITHER == 3:
			FRAC_ORDER = 3
		else:
			FRAC_ORDER = 2
		self.setWord(FRAC_ORDER, 'FRAC_ORDER')

		# Here is the booting sequence after changing frequency according to 8.5.3

		# 1. (optional) If the OUTx_MUX State is changing, program Register R5
		# 2. (optional) If the VCO_DIV state is changing, program Register R3.
		# See VCO_DIV[4:0] - VCO Divider Value if programming a to a value of 4.
		if VCO_DIV == None:
			self.setWord(0, 'OUTA_MUX')
			self.setWord(0, 'OUTB_MUX')
		else:
			self.setWord(1, 'OUTA_MUX')
			self.setWord(1, 'OUTB_MUX')
			VCO_DIV = VCO_DIV / 2 - 1
			self.setWord(VCO_DIV, 'VCO_DIV')

		# 3. (optional) If the MSB of the fractional numerator or charge pump gain
		# is changing, program register R1

		PLL_NUM_H = (PLL_NUM & 0b1111111111000000000000) >> 12
		PLL_NUM_L =  PLL_NUM & 0b0000000000111111111111

		self.setWord(PLL_DEN,   'PLL_DEN')
		self.setWord(PLL_NUM_H, 'PLL_NUM_H')
		self.setWord(PLL_NUM_L, 'PLL_NUM_L')
		self.setWord(PLL_N,     'PLL_N')

		# 4. (Required) Program register R0
		# Activate frequency calibration
		self.setWord(0, 'NO_FCAL')

		# Sleep 20ms
		time.sleep(0.02)

		self.setWord(0, 'NO_FCAL')

		if self.getDiagnoses('LD_PINSTATE'):
			return True
		else:
			logging.error('LMX2581 not locked')
			return False
		

	def write(self, data, addr=None, mask=None):
		if mask != None and addr != None:
			r = self.read(addr)
			r = self._set(r, data, mask)
			self.write(r, addr)
		elif mask == None and addr != None:
			cmd = (data & 0xfffffff0) | (addr & 0xf)
			self._write(cmd)
		elif mask == None and addr == None:
			self._write(data)
		else:
			raise ValueError("Invalid parameters")

	def read(self, addr):
		rid = self.getRegId('RDADDR')
		# Tell LMX2581 which register to read
		r06 = self._set(0x400, addr, self.DICTS[rid]['RDADDR'])
		self.write(r06, rid)
		# Read the register by issuing a dummy write
		self.write(self.CMD10)
		return self._read()

	def _set(self, d1, d2, mask=None):
		# Update some bits of d1 with d2, while keep other bits unchanged
		if mask:
			d1 = d1 & ~mask
			d2 = d2 * (mask & -mask)
		return d1 | d2

	def _get(self, data, mask):
		data = data & mask
		return data / (mask & -mask)

	def reset(self):
		self.setWord(1,'RESET')

	def getDiagnoses(self,name=None):
		diag = self.read(6)
		if name:
			if name not in self.MASK_DIAG:
				raise ValueError("Invalid parameter")
			mask = self.MASK_DIAG.get(name)
			return self._get(diag, mask)
		else:
			result = {}
			for name,mask in self.MASK_DIAG.items():
				result[name] = self._get(diag, mask)
			return result

	def getRegister(self,rid=None):
		if rid==None:
			return [self.getRegister(regId) for regId in self.A_DICT_LIST]
		elif rid in self.A_DICT_LIST:
			rval = self.read(rid)
			return {name: self._get(rval,mask) for name, mask in self.DICTS[rid].items()}
		else:
			raise ValueError("Invalid parameter")

	def getWord(self,name):
		rid = self.getRegId(name)
		rval = self.read(rid)
		return self._get(rval,self.DICTS[rid][name])

	def setWord(self,value,name):
		rid = self.getRegId(name)
		self.write(value,rid,self.DICTS[rid][name])

	def getRegId(self,name):
		rid = None
		for d in [self.DICTS[a] for a in self.A_DICT_LIST]:
			if name in d:
				rid = self.DICTS.index(d)
				break
		if rid == None:
			raise ValueError("Invalid parameter")
		return rid

	def loadCfgFromFile(self,filename):
		f = open(filename)
		lines = [l.split("\t") for l in f.read().splitlines()]
		regs = [int(l[1].rstrip(),0) for l in lines]
		for reg in regs:
			self.write(reg)
				
		if self.getDiagnoses('LD_PINSTATE'):
			return True
		else:
			logging.error('LMX2581 not locked')
			return False