chore: baseline existing CI-V suite before RepeaterBook integration

civ.py

@@ -0,0 +1,95 @@
+"""
+Pure CI-V codec for the ICOM ID-5100 — no I/O, no dependencies.
+
+CI-V frame:  FE FE <to> <from> <cmd> [sub] [data...] FD
+All multi-byte numeric fields are BCD. Frequency is 5-byte little-endian BCD;
+levels/meters are 2-byte big-endian BCD in the range 0000..0255.
+"""
+from collections import namedtuple
+
+RADIO_ADDR = 0x8C   # ID-5100 default CI-V address
+CTRL_ADDR = 0xE0    # this controller's address
+PREAMBLE = b"\xFE\xFE"
+EOM = 0xFD
+
+# Command bytes (generic ICOM CI-V; verified subset for the ID-5100)
+CMD_READ_FREQ = 0x03
+CMD_READ_MODE = 0x04
+CMD_SET_FREQ = 0x05
+CMD_SET_MODE = 0x06
+CMD_LEVEL = 0x14    # sub 0x01 = AF (volume), 0x03 = squelch level
+CMD_METER = 0x15    # sub 0x01 = squelch status, 0x02 = S-meter
+SUB_AF = 0x01
+SUB_SQL_LEVEL = 0x03
+SUB_SQL_STATUS = 0x01
+SUB_SMETER = 0x02
+
+Frame = namedtuple("Frame", "to frm cn data")
+
+
+def freq_to_bcd(hz):
+    """Hz -> 5-byte little-endian BCD."""
+    digits = f"{hz:010d}"  # 10 decimal digits (up to 9.999 GHz)
+    out = bytearray()
+    # pairs from least significant; byte0 holds the lowest two digits
+    for i in range(0, 10, 2):
+        hi = digits[8 - i]
+        lo = digits[9 - i]
+        out.append((int(hi) << 4) | int(lo))
+    return bytes(out)
+
+
+def bcd_to_freq(data):
+    """5-byte little-endian BCD -> Hz."""
+    hz = 0
+    for i, byte in enumerate(data[:5]):
+        ones = byte & 0x0F
+        tens = byte >> 4
+        hz += ones * (10 ** (2 * i)) + tens * (10 ** (2 * i + 1))
+    return hz
+
+
+def level_to_bcd(value):
+    """0..255 -> 2-byte BCD (e.g. 128 -> 01 28)."""
+    if not 0 <= value <= 255:
+        raise ValueError(f"level {value} out of range 0..255")
+    digits = f"{value:04d}"
+    return bytes([(int(digits[0]) << 4) | int(digits[1]),
+                  (int(digits[2]) << 4) | int(digits[3])])
+
+
+def bcd_to_level(data):
+    """2-byte BCD -> int 0..255."""
+    value = 0
+    for byte in data[:2]:
+        value = value * 100 + (byte >> 4) * 10 + (byte & 0x0F)
+    return value
+
+
+def build_frame(cmd, data=b"", to=RADIO_ADDR, frm=CTRL_ADDR):
+    """Assemble FE FE <to> <from> <cmd> [data] FD."""
+    return PREAMBLE + bytes([to, frm, cmd]) + bytes(data) + bytes([EOM])
+
+
+def parse_frames(buf):
+    """Extract complete CI-V frames from a byte buffer, skipping noise/echo.
+
+    Returns a list of Frame(to, frm, cn, data) where `data` is everything
+    between the command byte and the EOM (so it includes any subcommand byte).
+    """
+    frames = []
+    i, n = 0, len(buf)
+    while i < n - 1:
+        if buf[i] == 0xFE and buf[i + 1] == 0xFE:
+            j = i + 2
+            while j < n and buf[j] != EOM:
+                j += 1
+            if j >= n:
+                break  # incomplete trailing frame
+            inner = buf[i + 2:j]
+            if len(inner) >= 3:
+                frames.append(Frame(inner[0], inner[1], inner[2], bytes(inner[3:])))
+            i = j + 1
+            continue
+        i += 1
+    return frames