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devices/dds_core: add frequency_to_ftw and ftw_to_frequency

This commit is contained in:
Sebastien Bourdeauducq 2014-10-13 17:05:35 +08:00
parent 5b05a3f75b
commit 74adb39157
1 changed files with 17 additions and 1 deletions
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18
artiq/devices/dds_core.py
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@ -25,6 +25,22 @@ class DDS(AutoContext):
kernel_attr = "previous_frequency"
@portable
def frequency_to_ftw(self, frequency):
"""Returns the frequency tuning word corresponding to the given
frequency.
"""
return int(2**32*frequency/self.dds_sysclk)
@portable
def ftw_to_frequency(self, ftw):
"""Returns the frequency corresponding to the given frequency tuning
word.
"""
return ftw*self.dds_sysclk/2**32
@kernel
def on(self, frequency):
"""Sets the DDS channel to the specified frequency and turns it on.
@ -47,7 +63,7 @@ class DDS(AutoContext):
# the same time.
fud_time = -1
syscall("dds_program", self.reg_channel,
int(2**32*frequency/self.dds_sysclk),
self.frequency_to_ftw(frequency),
fud_time)
self.previous_frequency = frequency
self.sw.on()