Echoing characters using font bitmaps in nasm

Does anybody know how to read characters from a keyboard and echoes them on the screen using nasm assembler? The thing is I have a set of font bitmaps which I have to use to echo whatever character the user enters on the screen but I have no clue how to do that.
Please somebody help me out!And how can I get the ascii value of the character from the scan code  of the key?
Thank you
debriscaAsked:
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terageekCommented:
Read characters from the keyboard using DOS interrupts to poll the keyboard.

Convert scan codes into ascii with a lookup table.  Create a table such that lookup_table[scan_code] = ascii value.

If you are echoing text to the screen in a text mode, there are DOS interrupts which will put a character to the screen.  If you are in GFX mode, then you will need to to a blt (block transfer) to copy the bitmap of the appropriate character to the screen.  Again, you can use a lookup table to go from an ascii character to the offset in your font bitmap where the character begins.

Does this help at all?  Do you need any more details?
bbaoIT ConsultantCommented:
read input from keyboard:
you can use interrupt 16h, function 00h to read the keyboard. this gets a key from the keyboard buffer. if there isn't one, it waits until there is. it returns the scan code in AH and the ASCII translation in AL.

xor ah,ah  ; function 00h - get character
int 16h      ; interrupt 16h

scan code table:
http://members.iweb.net.au/~pstorr/pcbook/book3/scancode.htm

hope it helps,
bbao

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