Using a special character named <Esc>, it is possible to add some format codes that will modify the console text format options.
The ANSI/VT100 commands are the same on any terminal, the only thing that may differ is the way to obtain the Escape char. Let's keep it short and simple : on Bash, it's ASCII code 27.
So, let's just add a 27 char and then play with control sequences.
Let's start
Memory: empty
Cursor: first cell
Input: any text
Process
generate 9
use this 9 to generate 27, 90, 45 and 108
change this to 27, 91, 49 and 109
this is [1m chars
print those chars : style is bold !!!
read a char and print while it's not null
print ASCII code 10 (newline)
change 49 to 48 and re-print those chars
style reset to normal
Code
+++++++++[->+++>++++++++++ generate the desired numbers
>+++++>++++++++++++<<<<] ** part 2 **
>>+>++++>+<<<[.>] print escape control sequence
,[., print all chars from input]
++++++++++.[-] print newline
<<-<<[.>] print reset escape control sequence