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trx_toolkit: define TRXDv2 PDUs using declarative codec 

Change-Id: If356d285006c0b9b57879d0499b8144eca820cab
Related: OS#4006, SYS#4895
This commit is contained in:
Vadim Yanitskiy 2021-03-11 21:36:29 +01:00
parent 7c3a566b52
commit d4900f93ee
1 changed files with 88 additions and 6 deletions
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94
src/target/trx_toolkit/trxd_proto.py
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@ -30,12 +30,20 @@ import codec
class Header(codec.BitFieldSet):
''' Header constructor for TRXD PDUs. '''
def __init__(self, ver: int):
codec.BitFieldSet.__init__(self, len=1, set=(
codec.BitField('ver', bl=4, val=ver),
codec.BitField.Pad(bl=1), # RFU
def __init__(self, ver: int, batched: bool = False):
f = [ # Dynamically generated field list
codec.BitField('ver', bl=4, val=ver) if not batched
else codec.BitField.Spare(bl=4), # RFU
codec.BitField.Spare(bl=1),
codec.BitField('tn', bl=3),
))
]
if ver >= 2: # TRXDv2 and higher
f.append(codec.BitField('batch', bl=1))
f.append(codec.BitField.Spare(bl=1))
f.append(codec.BitField('trxn', bl=6))
codec.BitFieldSet.__init__(self, set=tuple(f))
class MTS(codec.BitFieldSet):
''' Modulation and Training Sequence. '''
@ -53,8 +61,10 @@ class MTS(codec.BitFieldSet):
GMSK_BURST_LEN = 148
if (mod >> 2) in (0b00, 0b11): # GMSK or AQPSK
if (mod >> 2) == 0b00: # GMSK
return 1 * GMSK_BURST_LEN
elif (mod >> 2) == 0b11: # AQPSK
return 2 * GMSK_BURST_LEN
elif (mod >> 1) == 0b010: # 8-PSK
return 3 * GMSK_BURST_LEN
elif (mod >> 1) == 0b100: # 16QAM
@ -65,6 +75,35 @@ 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. '''
@ -118,3 +157,46 @@ class PDUv1Tx(PDUv0Tx):
def __init__(self, *args, **kw):
PDUv0Tx.__init__(self, *args, **kw)
self.STRUCT[0]._fields[0].val = 1
class PDUv2Rx(codec.Envelope):
class BPDU(codec.Envelope):
''' Batched PDU part. '''
STRUCT = (
Header(ver=2, batched=True),
MTS(),
codec.Uint('rssi', mult=-1),
codec.Int16BE('toa256'),
codec.Int16BE('cir'),
BurstBits('soft-bits'),
)
STRUCT = (
Header(ver=2),
MTS(),
codec.Uint('rssi', mult=-1),
codec.Int16BE('toa256'),
codec.Int16BE('cir'),
codec.Uint32BE('fn'),
BurstBits('soft-bits'),
codec.Sequence(item=BPDU()).f('bpdu'),
)
class PDUv2Tx(codec.Envelope):
class BPDU(codec.Envelope):
''' Batched PDU part. '''
STRUCT = (
Header(ver=2, batched=True),
MTS(),
Power(),
BurstBits('hard-bits'),
)
STRUCT = (
Header(ver=2),
MTS(),
Power(),
codec.Uint32BE('fn'),
BurstBits('hard-bits'),
codec.Sequence(item=BPDU()).f('bpdu'),
)