trx_toolkit: change coding of 'PWR' and 'SCPIR' fields

During an internal discussion, it was decided to keep field 'PWR'
as-is and move 'SCPIR' into a separate octet.  This is easier to
parse, less confusing, and would save us some CPU cycles.

Change-Id: I482f72fd9305c51f43a0339d03904fb693d90ac9
Related: OS#4006, SYS#4895
This commit is contained in:
Vadim Yanitskiy 2021-04-14 04:30:08 +02:00
parent d4900f93ee
commit 393158ac08
1 changed files with 6 additions and 31 deletions

View File

@ -75,35 +75,6 @@ class MTS(codec.BitFieldSet):
return 1 * GMSK_BURST_LEN
raise ValueError('Unknown modulation type')
class Power(codec.Codec):
''' SCPIR and Tx power reduction (TRXDv2 and higher).
+-----------------+---------------------------------+
| 7 6 5 4 3 2 1 0 | Description |
+-----------------+---------------------------------+
| . . . . x x x x | Power REDuction (in 2 dB steps) |
+-----------------+---------------------------------+
| . x x x . . . . | SCPIR value (in 2 dB steps) |
+-----------------+---------------------------------+
| x . . . . . . . | SCPIR sign indicator |
+-----------------+---------------------------------+
'''
def from_bytes(self, vals: dict, data: bytes) -> int:
blob = ord(data) # Convert a byte to an int
vals['red'] = (blob & 0b1111) * 2
vals['scpir'] = ((blob >> 4) & 0b111) * 2
if blob & (1 << 7): # negative sign
vals['scpir'] *= -1
return 1
def to_bytes(self, vals: dict) -> bytes:
blob = (vals['red'] & 0b1111) \
| (abs(vals['scpir']) << 4) // 2 \
| (0x80 if (vals['scpir'] < 0) else 0x00)
return bytes((blob,))
class BurstBits(codec.Buf):
''' Soft-/hard-bits with variable length. '''
@ -188,14 +159,18 @@ class PDUv2Tx(codec.Envelope):
STRUCT = (
Header(ver=2, batched=True),
MTS(),
Power(),
codec.Uint('pwr'),
codec.Int('scpir'),
codec.Spare(len=3),
BurstBits('hard-bits'),
)
STRUCT = (
Header(ver=2),
MTS(),
Power(),
codec.Uint('pwr'),
codec.Int('scpir'),
codec.Spare(len=3),
codec.Uint32BE('fn'),
BurstBits('hard-bits'),
codec.Sequence(item=BPDU()).f('bpdu'),