IOT Multiple Choice Questions on “USB Bootloader”.
1. Boot loader consists of __________ number of components.
a) 4 components
b) 2 components
c) 3 components
d) 5 components
Answer: c
Clarification: The boot loader consists of the following components:
–> Target MCU
–> Master programmer
–> Data source.
2. All silicon labs SiMxxxxx MCUs with Flash memory are self-programmable.
a) True
b) False
Answer: a
Clarification: All silicon labs SiMxxxxx MCUs with Flash memory are self-programmable, ie., code running on the MCUs can erase and write other parts of the code memory.
3. If the device is programmed with a bootloader, the application image is loaded in _________ interface.
a) UART
b) USB
c) SPI
d) I2C
Answer: b
Clarification: An uninitialized device requires the bootloader to be flashed over the debug interface. Once the device is programmed with a bootloader, the application image is loaded in USB interface.
4. Application/s that provide to test the bootloader functionality.
a) Blinky_Fast and B.inky-Medium
b) Only Blinky_slow
c) Only Blinky_Fast
d) Blinky_Fast and Blinky_Slow
Answer: d
Clarification: There are two example applications provided to test out the bootloader functionality:
–> Blinky_Fast
–> Blinky_Slow.
5. _________ command should be performed to very that the firmware image is Blinky_fast.
a) Query
b) Reset
c) Upload
d) Download
Answer: a
Clarification: Query command is performed and we have to verify that the sAppName of the loaded firmware image is Blinky_Fast.
6. Which switch should be pressed to perform all commands?
a) Up switch
b) Push
c) Down switch
d) Reset switch
Answer: d
Clarification: Force the device into bootloader mode by holding down sw2 and pressing and releasing reset switch to perform a query, upload, or download command on the device.
7. DFU stands for Device Firmware Update.
a) True
b) False
Answer: a
Clarification: The file manager and DFU state machine are imported unmodified from the framework software.
8. When is DEVICE_Init called?
a) Upload
b) Reset
c) Download
d) Query
Answer: b
Clarification: The DEVICE_Init routine is called after each device reset and is responsible for initializing the device and checking for the appropriate trigger sources.
9. DEVICE_Init performs what?
a) Disabling watchdog timer and disabling APB clock
b) Enabling APB clock and enabling watchdog timer
c) Disabling watchdog timer and enabling APB clock
d) Disabling APB clock and enabling watchdog timer
Answer: c
Clarification: The DEVICE_Init routine performs the following functions:
–> Disables the watchdog timer and enables the APB clock
–> Determines the amount of Flash and RAM in the device
–> Check all internal and external automatic trigger sources.
10. DEVICE_Restore routine restores all the device registers modified by DEVICE_Init to their reset values.
a) True
b) False
Answer: a
Clarification: DEVICE_Restore routine restores all the device registers modified by DEVICE_Init to their reset values. This includes starting the watchdog timer and restoring the APB clock gates back to their reset value.