Application description

AN3259

8/25

Doc ID 17835 Rev 1

3.3.2

Communication sequence between the STM8S-DISCOVERY

and the terminal

1.

The STM8S microcontroller sends the character string ‘Enter your choice’ to the PC

terminal emulator software.

2.

The terminal displays the string ‘Enter your choice’.

3.

The user strikes key 2 on his keyboard.

4.

The terminal emulator software sends back the corresponding ASCII code (0x52) to the

microcontroller (see Appendix A: Standard ASCII character codes).

5.

The microcontroller decodes the data received, sends back the code 0x52 for it to be

displayed on the terminal, and stores the value ‘2’ in memory.

6.

The terminal emulator software receives the code 0x52 and displays ‘2’.

7.

The user strikes the Return key.

8.

The terminal emulator software send back the code 0x0D corresponding to carriage

return (see Appendix A: Standard ASCII character codes).

9.

The STM8S105C6T6 microcontroller decode the data received, sends back the code

0x0D for it to be displayed it on the terminal, and performs the action associated to

option 2.