import can
import time

# === 修改成你的介面 ===
# 如果你用 socketCAN-tcp (slcand) 綁到 can0：
# bus = can.interface.Bus(bustype="socketcan", channel="can0", bitrate=500000)

# 如果是 PCAN (Peak)：
# bus = can.interface.Bus(bustype="pcan", channel="PCAN_USBBUS1", bitrate=500000)

# 如果是 Kvaser：
# bus = can.interface.Bus(bustype="kvaser", channel=0, bitrate=500000)

# 這裡先假設你用 socketcan
bus = can.interface.Bus(bustype="socketcan", channel="can0", bitrate=500000)

# === 設定參數 ===
node_id = 1
cob_id = 0x200 + node_id   # PLC 的 RxPDO1
value = 1234               # 要送的整數值 (INT16)

# 轉成小端 (因為 PLC 是 little endian)
data_bytes = value.to_bytes(2, byteorder="little", signed=True)

# 塞進 CAN 幀
msg = can.Message(arbitration_id=cob_id, data=data_bytes, is_extended_id=False)

# 傳送多次測試
for i in range(10):
    try:
        bus.send(msg)
        print(f"Sent {value} to PLC (COB-ID=0x{cob_id:X})")
    except can.CanError:
        print("Message NOT sent")
    time.sleep(1)