Add SET_SATELLITE_INFO (opcode 77) request + reply body structs

src/benlink/protocol/command/message.py

@@ -30,6 +30,7 @@
 from .phone_status import SetPhoneStatusBody, SetPhoneStatusReplyBody
 from .status import GetHtStatusBody, GetHtStatusReplyBody
 from .position import GetPositionBody, GetPositionReplyBody
+from .satellite_info import SetSatelliteInfoBody, SetSatelliteInfoReplyBody
 
 
 class CommandGroup(IntEnum):
@@ -184,6 +185,11 @@ def body_disc(m: Message, n: int):
                     out = GetHtStatusReplyBody if m.is_reply else GetHtStatusBody
                 case BasicCommand.GET_POSITION:
                     out = GetPositionReplyBody if m.is_reply else GetPositionBody
+                case BasicCommand.SET_SATELLITE_INFO:
+                    out = (
+                        SetSatelliteInfoReplyBody if m.is_reply
+                        else SetSatelliteInfoBody
+                    )
                 case _:
                     return bf_bytes(n // 8)
         case CommandGroup.EXTENDED:
@@ -223,6 +229,8 @@ def body_disc(m: Message, n: int):
     GetHtStatusReplyBody,
     GetPositionReplyBody,
     GetPositionBody,
+    SetSatelliteInfoBody,
+    SetSatelliteInfoReplyBody,
 ]
 
 

src/benlink/protocol/command/satellite_info.py

@@ -0,0 +1,46 @@
+from __future__ import annotations
+from .bitfield import Bitfield, bf_int, bf_int_enum, bf_lit_int, bf_str, bf_map
+from .common import ReplyStatus
+import typing as t
+
+
+class CountdownMapper:
+    """16-bit seconds-until-event; 0xFFFF == unknown/none, 0 == now/past."""
+
+    def forward(self, x: int) -> int | None:
+        return x if x != 0xFFFF else None
+
+    def back(self, y: int | None) -> int:
+        return y if y is not None else 0xFFFF
+
+
+class SetSatelliteInfoBody(Bitfield):
+    # Fixed 30-byte payload. Name occupies the first 20 bytes; the firmware
+    # app encodes it as GB2312 (identical to ASCII for names like "ISS",
+    # "AO-91"; diverges only for non-ASCII characters). NUL-padded.
+    name: str = bf_str(20, "gb2312")
+
+    # Azimuth, integer degrees 0-359 (9 bits), then 7 reserved bits.
+    azimuth: int = bf_int(9)
+    _pad_az: t.Literal[0] = bf_lit_int(7, default=0)
+
+    # Elevation, integer degrees (8 bits, written unsigned by the app's
+    # tracking path), then 8 reserved bits.
+    elevation: int = bf_int(8)
+    _pad_el: t.Literal[0] = bf_lit_int(8, default=0)
+
+    # Slant range to the satellite, km (firmware clamps >65535 to 0).
+    range_km: int = bf_int(16)
+
+    # Satellite orbital altitude, km (firmware clamps >65535 to 0).
+    altitude_km: int = bf_int(16)
+
+    # Seconds until the next tracked event; 0xFFFF == unknown.
+    countdown_secs: int | None = bf_map(bf_int(16), CountdownMapper())
+
+
+class SetSatelliteInfoReplyBody(Bitfield):
+    # Inferred from the SET_* convention (bare ReplyStatus ack, like
+    # SetPhoneStatusReplyBody). No dedicated reply parser is present in the
+    # decompile; worth confirming against one on-air capture.
+    reply_status: ReplyStatus = bf_int_enum(ReplyStatus, 8)