問題背景：
硬件環境：freescale-S08DZ60+TJA1051T
CAN分析儀：ZLG-USBCANI
硬件無異常，驅動在上一版本電路測試過，可用
問題描述：
freescale-S08DZ60接TJA1051T，調試CAN驅動，
TJA1051T無輸出，
解決過程：
CAN-H和CAN-L輸出正弦波，單片機CAN-TX輸出規律脈沖段
代碼調試，裝填完三個CAN發送緩沖區后顯示CAN發送緩沖區滿，
未觸發CAN發送中斷
結合示波器波形，CAN數據發送動作未執行
結合網絡資料顯示，出現CAN緩沖器滿但無數據發出的情況可能為CAN節點異常
CAN自收發測試正常，
綜上可以判斷，問題出現在硬件，CAN收發器異常
回到原點，發現
CAN收發器焊接TJA1051T/3
經查閱手冊，該芯片
與TJA1051T不兼容，更換后CAN收發正常
經驗總結：
1，
TJA1051T是TJA1050的升級版本
2，
TJA1051T有三個版本：
TJA1051T、
TJA1051T/3(
TJA1051TK/3
)、
TJA1051T/E
唯一的區別是引腳5的功能
TJA1051T 100%向后兼容TJA1050
TJA1051T/3和TJA1051TK/3允許與3V單片機直連
TJA1051T/E允許接收器切換到低電流離線模式
摘自數據手冊
The TJA1051 is a high-speed CAN stand-alone transceiver with Silent mode. It combines
the functionality of the TJA1050 transceiver with improved EMC and ESD handling
capability. Improved slope control and high DC handling capability on the bus pins
provides additional application flexibility.
The TJA1051 is available in three versions, distinguished only by the function of pin 5:
• The TJA1051T is 100 % backwards compatible with the TJA1050
• The TJA1051T/3 and TJA1051TK/3 allow for direct interfacing to microcontrollers with
supply voltages down to 3 V
• The TJA1051T/E allows the transceiver to be switched to a very low-current Off mode.
V
IO
supply pin
There are three versions of the TJA1051 available, only differing in the function of a single
pin. Pin 5 is either an enable control input (EN), a V
IO
supply pin or is not connected.
Pin V
IO
on the TJA1051T/3 and TJA1051TK/3 should be connected to the microcontroller
supply voltage (see
Figure 6
)
. This will adjust the signal levels of pins TXD, RXD and S to
the I/O levels of the microcontroller. For versions of the TJA1051 without a V
IO
pin, the V
IO
input is internally connected to V
CC
. This sets the signal levels of pins TXD, RXD and S to
levels compatible with 5 V microcontrollers.
