R divider configuration, etc.

This commit is contained in:
Michael Ossmann
2012-05-01 07:49:19 -06:00
parent b43c8a58aa
commit 22fc4dfeab

View File

@ -43,6 +43,7 @@
import sys import sys
from pyBusPirateLite.I2C import * from pyBusPirateLite.I2C import *
from math import log
if len(sys.argv) < 2: if len(sys.argv) < 2:
print('Usage: %s <path to serial device>' % (sys.argv[0],)) print('Usage: %s <path to serial device>' % (sys.argv[0],))
@ -80,12 +81,13 @@ def write_registers(first_register_number, values):
i2c.bulk_trans(len(data), data) i2c.bulk_trans(len(data), data)
i2c.send_stop_bit() i2c.send_stop_bit()
def set_multisynth_parameters(ms_n, p1, p2, p3): # r is the R output divider (should be 1, 2, 4, 8. . .)
def set_multisynth_parameters(ms_n, p1, p2, p3, r):
register_number = 42 + (ms_n * 8) register_number = 42 + (ms_n * 8)
values = ( values = (
(p3 >> 8) & 0xFF, (p3 >> 8) & 0xFF,
(p3 >> 0) & 0xFF, (p3 >> 0) & 0xFF,
(0 << 4) | (0 << 2) | ((p1 >> 16) & 0x3), (int(log(r, 2)) << 4) | (0 << 2) | ((p1 >> 16) & 0x3),
(p1 >> 8) & 0xFF, (p1 >> 8) & 0xFF,
(p1 >> 0) & 0xFF, (p1 >> 0) & 0xFF,
(((p3 >> 16) & 0xF) << 4) | (((p2 >> 16) & 0xF) << 0), (((p3 >> 16) & 0xF) << 4) | (((p2 >> 16) & 0xF) << 0),
@ -94,15 +96,13 @@ def set_multisynth_parameters(ms_n, p1, p2, p3):
) )
write_registers(register_number, values) write_registers(register_number, values)
# Get the appropriate P1 setting for a given frequency.
# Assumes VCO is 800 MHz and you want integer division and R=4.
def integer_p1(frequency):
return int(800e6/frequency) * 128 - 512
def set_codec_rate(frequency): def set_codec_rate(frequency):
ms1_p1_values = { set_multisynth_parameters(1, integer_p1(frequency * 4), 0, 0, 4)
8.0e6: 12288,
10.0e6: 9728,
12.5e6: 7680,
16.0e6: 5888,
20.0e6: 4608,
}
set_multisynth_parameters(1, ms1_p1_values[frequency], 0, 0)
print('Configuring Si5351...') print('Configuring Si5351...')
@ -138,16 +138,20 @@ write_registers(26, (0x00, 0x00, 0x00, 0x0E, 0x00, 0x00, 0x00, 0x00))
# MultiSynth 0 # MultiSynth 0
# This is the source for the MAX2837 clock input. # This is the source for the MAX2837 clock input.
set_multisynth_parameters(0, 2048, 0, 0) # 40MHz set_multisynth_parameters(0, integer_p1(40e6), 0, 0, 1) # 40MHz
# MultiSynth 1 # MultiSynth 1
set_codec_rate(20e6) set_codec_rate(20e6)
# MultiSynth 4 # MultiSynth 4
# This is the source for the LPC43xx external clock input. # This is the source for the LPC43xx external clock input.
set_multisynth_parameters(4, 8021, 1, 3) # 12MHz set_multisynth_parameters(4, 8021, 1, 3, 1) # 12MHz
#set_multisynth_parameters(4, 4608, 0, 0) # 20MHz #set_multisynth_parameters(4, integer_p1(20e6), 0, 0, 1) # 20 MHz
#set_multisynth_parameters(4, 3584, 0, 0) # 25MHz #set_multisynth_parameters(4, integer_p1(80e6), 0, 0, 4) # 20 MHz using R=4
#set_multisynth_parameters(4, 3584, 0, 0, 1) # 25MHz
# MultiSynth 6/7 R dividers
write_registers(92, 0x00)
# Registers 16 through 23: CLKx Control # Registers 16 through 23: CLKx Control
# CLK0: # CLK0:
@ -174,7 +178,7 @@ set_multisynth_parameters(4, 8021, 1, 3) # 12MHz
write_registers(16, (0x4F, 0x4F, 0x80, 0x80, 0x0F, 0x80, 0x80, 0x80)) write_registers(16, (0x4F, 0x4F, 0x80, 0x80, 0x0F, 0x80, 0x80, 0x80))
# Enable CLK outputs 0, 1, 4 only. # Enable CLK outputs 0, 1, 4 only.
write_registers(3, 0xEC) write_registers(3, 0xFF ^ 0b00010011)
raw_input("<return> to quit...") raw_input("<return> to quit...")