硬件环境为蜂鸟实验板和调试器。修改e203的代码，然后综合生成*.mcs文件，下载至开发板，然后编写软件代码下载到开发板时出现如下现象。起初下载软件程序至开发板，upload成功，screen打印出结果。但多下载几次或者断电后重新下载软件代码至开发板，出现错误，错误如下：

Info : Exposing additional CSR 3067

Info : Exposing additional CSR 3068

Info : Exposing additional CSR 3069

Info : Exposing additional CSR 3070

Info : Exposing additional CSR 3071

Error: Timed out waiting for debug int to clear.Increase timeout with riscv set_command_timeout_sec.

Error: Debug interrupt didn't clear.

Error: Debug RAM 0x0: 0xfff04493

Error: Debug RAM 0x1: 0x01f4d493

Error: Debug RAM 0x2: 0x40902023

Error: Debug RAM 0x3: 0x01f4d493

Error: Debug RAM 0x4: 0x40902223

Error: Debug RAM 0x5: 0x3f00006f

Error: Debug RAM 0x6: 0x060c1218

Error: Debug RAM 0x7: 0x00000000

Error: Debug RAM 0x8: 0x00000000

Error: Debug RAM 0x9: 0x00000000

Error: Debug RAM 0xa: 0x00000000

Error: Debug RAM 0xb: 0x00000000

Error: Debug RAM 0xc: 0x00000000

Error: Debug RAM 0xd: 0x00000000

Error: Debug RAM 0xe: 0x00000000

Error: Debug RAM 0xf: 0x00000000

Error: Timed out waiting for debug int to clear.Increase timeout with riscv set_command_timeout_sec.

Error: Debug interrupt didn't clear.

Error: Debug RAM 0x0: 0xfff04493

Error: Debug RAM 0x1: 0x01f4d493

Error: Debug RAM 0x2: 0x40902023

Error: Debug RAM 0x3: 0x01f4d493

Error: Debug RAM 0x4: 0x40902223

Error: Debug RAM 0x5: 0x3f00006f

Error: Debug RAM 0x6: 0x060c1218

Error: Debug RAM 0x7: 0x00000000

Error: Debug RAM 0x8: 0x00000000

Error: Debug RAM 0x9: 0x00000000

Error: Debug RAM 0xa: 0x00000000

Error: Debug RAM 0xb: 0x00000000

Error: Debug RAM 0xc: 0x00000000

Error: Debug RAM 0xd: 0x00000000

Error: Debug RAM 0xe: 0x00000000

Error: Debug RAM 0xf: 0x00000000

Error: Failed to discover xlen; word0=0xfff04493, word1=0x1f4d493, exception=0x60c1218

Error: Debug RAM 0x0: 0xfff04493

Error: Debug RAM 0x1: 0x01f4d493

Error: Debug RAM 0x2: 0x40902023

Error: Debug RAM 0x3: 0x01f4d493

Error: Debug RAM 0x4: 0x40902223

Error: Debug RAM 0x5: 0x3f00006f

Error: Debug RAM 0x6: 0x060c1218

Error: Debug RAM 0x7: 0x00000000

Error: Debug RAM 0x8: 0x00000000

Error: Debug RAM 0x9: 0x00000000

Error: Debug RAM 0xa: 0x00000000

Error: Debug RAM 0xb: 0x00000000

Error: Debug RAM 0xc: 0x00000000

Error: Debug RAM 0xd: 0x00000000

Error: Debug RAM 0xe: 0x00000000

Error: Debug RAM 0xf: 0x00000000

Info : Listening on port 3333 for gdb connections

Error: Target not examined yet

Warn : Flash driver of my_first_flash does not support free_driver_priv()

localhost:3333: Connection timed out.

"monitor" command not supported by this target.

"monitor" command not supported by this target.

You can't do that when your target is `exec'