I am giving my comments solely on the basis of the diagrams you have posting, without understanding the functionality.
I think the correct one is in post #8 pic 1 (so it is a 3:1 MUX again), because the data_out of the char_ram should be going to the display unit.
hello
yes that is true, but data_out of char ram need data from somewhere for example keyboard ,ic2, data memory
oh my god i dont know, i am also a beginner, but if he need from data from keyboard need first data of input keyboard to be stored in data_mem or direct like first
example in begin post #post 1 from keyboard to char ram to display or may 2 from data_mem and direct to char ram(if it so why is not good pic 2)
what do you think? how it should be?
because
i am reading that book, like exercise in book he say
Design a computer system that contains a CPU, instruction memory, data memory, character
RAM (text mode), font table, PS/2 keyboard interface, VGA interface, and an I2C controller
with an I2C EEPROM
cpu = d_f_mem is data load, d_t_mem store data to, io_rdn is i/o read, io_wrn is i/o write, wvram video ram write, m_adder memory adress, write data memory write,
man how to do it, i am amater:bang: