最近在学习stm32单片机，在该单片机上跑μc/os，执行多任务。
由于刚刚接触到该芯片，所以有许多基础的问题会遇到。
在安装好j-flash之后，通过j-flash下载程序到stm32。
选择好option->project setting下面的配置之后，target->connection，打印出如下调试信息：
Connecting ...
- Connecting via USB to J-Link device 0
- J-Link firmware: V1.20 (J-Link V9 compiled Apr 21 2015 18:10:40)
- Target interface speed: 1000 kHz (Auto)
- Initializing CPU core (Init sequence) ...
- Initialized successfully
- Target interface speed: 1000 kHz (Auto)
- WARNING: Unexpected core ID. (Found: 0x00000000, Expected: 0x4BA00477, Mask: 0x0F000FFF)---没有读取到core ID
- J-Link found 0 JTAG device. Core ID: 0x00000000 (ARM9)---没有发现 JTAG设备
- Connected successfully----这里却提示连接成功
然后将.hex文件往STM32中下载的时候，提示如下信息：
Opening data file [output(mdk).hex] ...---打开文件
- Data file opened successfully (8256 bytes, 1 range, CRC = 0x5E6CC4EA)----打开文件成功
Auto programming target (8256 bytes, 1 range) ...---自动
- Unsecure chip ...
- Chip unsecured successfully
- Erasing affected sectors ...---擦除扇区
- WARNING: Unexpected core ID. (Found: 0x00000000, Expected: 0x4BA00477, Mask: 0x0F000FFF)--提示没有读到core ID
- ERROR: RAM check failed @ address 0x20000000.
- ERROR: Write: 0x03020100 07060504
- ERROR: Read: 0x00000000 00000000
- ERROR: (0 bytes of RAM have been checked successfully)
- ERROR: Failed to erase sectors
- De-initializing CPU core (Exit sequence) ...
- ERROR: Failed to auto program target---自动下载程序到目标失败
Disconnecting ...---断开连接
- Disconnected
但是，程序还是可以下载到STM32中。
目前没有找到问题出现在哪里，有哪位大神可否指点一二？