putchar

Prints a character on the screen using firmware routines.  This function is required by printf when we use C standard library.

C Definition

void putchar (char c)

Details

This function is required by C standard library to be able to use printf.  It defines a way to print a given character to the screen.  This version of the function makes use of firmware to print.

Known limitations

Firmware must be ENABLED to be able to use this function.

Side-effects

Calling this function with firmware disabled yields undefined behaviour, but normally leads to firmware being reenabled (unless 0xBB5A has been overwritten previously).

Destroyed Register values

AF, BC, DE, HL

Required memory

14 bytes

Time Measures

Case   | microSecs(us) | CPU Cycles
-------------------------------------
C Call |   16 + PC     |   64 + PC
-------------------------------------
Any    |    9 + PC     |   36 + PC
-------------------------------------

PC = Time used in the call to firmware Print Charater function

Prints a character on the screen using firmware routines.
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