1-100 (No.RA020)Descriptions of signal names(1) 33BT: BT/GPS IC 3.3V power supply(2) 18BT: BT/GPS IC 1.8V power supply(3) 33GPS: BT/GPS IC 3.3V power supply(4) TXD2: BT/GPS serial data line connected to UART TX of MPU/DSP IC (MPU/DSP to BT/GPS IC)(5) RXD2:BT/GPS serial data line connected to UART RX of MPU/DSP IC (MPU/DSP to BT/GPS IC)(6) 18BT_HCI_RX: BT/GPS serial data line connected to UART RX of BT/GPS IC (MPU to BT/GPS IC)(7) 18BT_HCI_TX: BT/GPS serial data line connected to UART TX of GPS IC (BT/GPS IC to MPU)(8) /BT_SHUTDOWN: BT/GPS active control of MPU/DSP IC (MPU/DSP to BT/GPS IC) High → Active, Low → ResetCheck the Main unit P CB.When an abnormalcondition is confirmed.When an abnormalcondition is confirmed.When an abnormalcondition is confirmed.When an abnormalcondition is confirmed.When a normalcondition is confirmed.When a normalcondition is confirmed.When a normalcondition is confirmed.When a normalcondition is confirmed.Verify the BT/GPS controlsignal (TXD2).CN735 (15 pin): Square waveformUART data of 3.3V logic.Baud rateDefault: 115.2kbpsAfter: 3.967Mbps.Verify the BT/GPS controlsignal(RXD2).CN735 (14 pin): Square waveformUART tada of 3.3V logic.Baud rate:Default: 115.2kbpsAfter: 3.967Mbps.Verify the BT/GPS controlsignal (G_RXD2).CP705, (3 pin):Square waveform UART dataof 1.8V logic.[The MPU/DSP IC is abnormal]Replace the PCB.Verify the BT/GPS controlsignal (G_TXD2).CP705 (2 pin):Square waveform UART dataof 3.3V logic.[The MPU/DSP IC is abnormal]Replace the PCB.[The TXD2 (18BT_HCI_RX)line circuit is faulty]Replace the CP705.[The RXD2 (18BT_HCI_TX)line circuit is faulty]Replace the CP705.[The MPU/DSP IC is abnormal]Replace the PCB.
