尊敬的TI工程师，你们好：
之前使用uniflash向自己画的cc3200板子烧写程序， 进行format的时候，打印出的调试信息如下：
[10:01:03] Begin Format operation.
[10:01:05] INFO: > Executing Operation: Connect
[10:01:05] DEBUG: waiting and clearing uart rx buffer
[10:01:07] INFO: setting break signal
[10:01:07] INFO: --- please restart the device ---
[10:01:07] DEBUG: wait for ack
[10:01:07] INFO: connection succeeded
[10:01:07] INFO: getting storage list
[10:01:07] DEBUG: wait for ack
[10:01:07] INFO: > Executing Operation: Init
[10:01:07] INFO: reading version info
[10:01:07] DEBUG: wait for ack
[10:01:07] INFO: DEVICE CC3200 ES1.33
[10:01:07] INFO: reading version info
[10:01:07] DEBUG: wait for ack
[10:01:07] DEBUG: Bootloader version is 2, 1, 4, 0
[10:01:07] DEBUG: It's a CC3200 device: PG1.33 or higher
[10:01:07] DEBUG: Switch UART pinmux to APPS
[10:01:07] DEBUG: wait for ack
[10:01:07] DEBUG: wait for ack
[10:01:08] DEBUG: Switch to NWP bootloader complete
[10:01:08] INFO: reading version info
[10:01:08] DEBUG: wait for ack
[10:01:23] DEBUG: UART timeout
[10:01:23] DEBUG: --- COM Port timeout on ACK read
[10:01:23] ERROR: No ACK
[10:01:38] DEBUG: UART timeout
[10:01:53] DEBUG: UART timeout
[10:01:53] ERROR: Error, version response should be 28 bytes, device is sending 0
[10:02:08] DEBUG: UART timeout
[10:02:08] ERROR: FAUpdateNwpBootloader failed - version info is incorrect
[10:02:08] FATAL: Error loading the bootloader. Error code: -3
[10:02:08] INFO: > Executing Operation: Disconnect
[10:02:08] DEBUG: disconnecting from device . . .
[10:02:08] DEBUG: wait for ack
[10:02:23] DEBUG: UART timeout
[10:02:23] DEBUG: --- COM Port timeout on ACK read
[10:02:23] Operation Format returned.
请教一下，此时在等待的ACK是什么，可能是由于什么原因引发的问题，请帮忙看一下，谢谢啦
