问题背景：
硬件环境：freescale-S08DZ60+TJA1051T
CAN分析仪：ZLG-USBCANI
硬件无异常，驱动在上一版本电路测试过，可用
问题描述：
freescale-S08DZ60接TJA1051T，调试CAN驱动，TJA1051T无输出，
解决过程：
CAN-H和CAN-L输出正弦波，单片机CAN-TX输出规律脉冲段
代码调试，装填完三个CAN发送缓冲区后显示CAN发送缓冲区满，未触发CAN发送中断
结合示波器波形，CAN数据发送动作未执行
结合网络资料显示，出现CAN缓冲器满但无数据发出的情况可能为CAN节点异常
CAN自收发测试正常，
综上可以判断，问题出现在硬件，CAN收发器异常
回到原点，发现CAN收发器焊接TJA1051T/3
经查阅手册，该芯片与TJA1051T不兼容，更换后CAN收发正常
经验总结：
1，TJA1051T是TJA1050的升级版本
2，TJA1051T有三个版本：TJA1051T、TJA1051T/3(TJA1051TK/3)、TJA1051T/E
唯一的区别是引脚5的功能
TJA1051T 100%向后兼容TJA1050
TJA1051T/3和TJA1051TK/3允许与3V单片机直连
TJA1051T/E允许接收器切换到低电流离线模式
摘自数据手册
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.
VIO 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 VIO supply pin or is not connected.
Pin VIO 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 VIO pin, the VIO
input is internally connected to VCC
. This sets the signal levels of pins TXD, RXD and S to
levels compatible with 5 V microcontrollers.
