uart: sample position nits, fix typo, float calculation awareness

This commit amends bd50ceb314e4. Fix a typo in a comment. Rephrase the
bit width percentage calculation such that readers remain aware of the
necessity for floating point math in sample position calculations. This
commit does not change behaviour, Python 3 always yields float results
for divisions. It's about raising awareness.

diff --git a/decoders/uart/pd.py b/decoders/uart/pd.py
index 9ffcb56e6d35cf06a1c7734e44086aefb2bca249..fd8254c217d1602e2c6c46b3d3b43e24a5239127 100644 (file)
--- a/decoders/uart/pd.py
+++ b/decoders/uart/pd.py
@@ -227,12 +227,13 @@ class Decoder(srd.Decoder):
         # Determine absolute sample number of a bit slot's sample point.
         # Counts for UART bits start from 0 (0 = start bit, 1..x = data,
         # x+1 = parity bit (if used) or the first stop bit, and so on).
-        # Accept a position in the range of 1.99% of the full bit width.
+        # Accept a position in the range of 1-99% of the full bit width.
         # Assume 50% for invalid input specs for backwards compatibility.
         perc = self.options['sample_point'] or 50
         if not perc or perc not in range(1, 100):
             perc = 50
-        bitpos = (self.bit_width - 1) * perc / 100
+        perc /= 100.0
+        bitpos = (self.bit_width - 1) * perc
         bitpos += self.frame_start[rxtx]
         bitpos += bitnum * self.bit_width
         return bitpos