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author | Uwe Hermann <uwe@hermann-uwe.de> | 2012-07-11 22:19:31 +0200 |
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committer | Uwe Hermann <uwe@hermann-uwe.de> | 2012-07-11 23:13:36 +0200 |
commit | 2fcd7c22852436c3226de9007e88cb305cce1b00 (patch) | |
tree | b1681936eec81e3bd91eb43fb395fc2bcf908aba /decoders/uart | |
parent | b5d3ea69628d49ab5b26e064559f7a237b46c086 (diff) | |
download | libsigrokdecode-2fcd7c22852436c3226de9007e88cb305cce1b00.tar.gz libsigrokdecode-2fcd7c22852436c3226de9007e88cb305cce1b00.zip |
srd: Performance improvements for various PDs.
Ignore/skip identical samples in most (low-level) PDs, as we're usually
(but not necessarily always) only interested in pin changes.
This yields a significant performance improvement for the PDs.
The mechanism was already used in the 'i2s', 'jtag', and 'lpc' PDs, but not
yet in all supported low-level decoders. The following PDs now also use
this mechanism: 'dcf77', 'i2c', 'spi', 'uart', and 'usb_signalling'.
Thanks Lars-Peter Clausen <lars@metafoo.de> for bringing this to our
attention.
Diffstat (limited to 'decoders/uart')
-rw-r--r-- | decoders/uart/uart.py | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/decoders/uart/uart.py b/decoders/uart/uart.py index bb4d9e6..92c105c 100644 --- a/decoders/uart/uart.py +++ b/decoders/uart/uart.py @@ -103,6 +103,7 @@ class Decoder(srd.Decoder): self.startsample = [-1, -1] self.state = ['WAIT FOR START BIT', 'WAIT FOR START BIT'] self.oldbit = [None, None] + self.oldpins = None def start(self, metadata): self.samplerate = metadata['samplerate'] @@ -265,7 +266,12 @@ class Decoder(srd.Decoder): def decode(self, ss, es, data): # TODO: Either RX or TX could be omitted (optional probe). - for (self.samplenum, (rx, tx)) in data: + for (self.samplenum, pins) in data: + + # Ignore identical samples early on (for performance reasons). + if self.oldpins == pins: + continue + self.oldpins, (rx, tx) = pins, pins # First sample: Save RX/TX value. if self.oldbit[RX] == None: |