Hangman in Assembly

[zellie]

My machine problem is to make a game of Hangman implemented in assembly language.

The specification of the program is for the the random words (to be used in the game) to come from an external word database (text file named worddb.txt).

How is that possible? How am I going to access and read the values in the an external file and incorporate it in my game?

I really have no clue. I am a beginner in assembly programming.

And if you know any website on this, it will be a big help.

p.s im using tasm.

[Aedan]

What platform do you need to write the code on? As you're using TAsm, I'm presuming you're writing it for DOS?

It is possible to access file under DOS - int 21 functions include such things.

What time period do you have to write the code in?

[zellie]

yes, i am writing it for dos.
i am only given 2 weeks to finish everything.

could you elaborate on the procedure (on how the access words in the textfile to my program)?

[Aedan]

You can use the int 21 functions in order to first open the file, and then to read data from the file.

For example

mov ax, 3d00 ; set ax to Open file for read
mov dx, xxx ; pointer to the filename - XXX
int 21

would result in DOS attempting to open the file. You want to check CF to see that the file exists - if it's not set, then AX will contain the filehandle you need for reading the file.

You can then do something like

mov bx, ax ; save the filehandle in bx
mov ah, 3f ; set ax for read file
mov cx, xx ; cx sets how many bytes you want to read
mov dx, xxx ; dx points to where you want the data
int 21

You'll want to check CF again. If CF is not set, then AX should equal the number of bytes read. If AX is zero, then you've hit the end of the file.

Once you have the file (or a section of the file), then you can run through it looking for the CR/LF sequence that terminates each line in the file.

[zellie]

i am finally able to access my external file. Although how can i individually access the words. As in per line.. because the words in the textfile seems to be considered as a whole.
For example,
red
yellow
blue

how am i suppose to access each word individually? Do i have to put them in an array?? ..

[zellie]

hmm.. what im trying to say is how to read word by word or line per line from the file ?

Since i need only one word at a time in the game.
hehe

[Aedan]

A text file is just a sequence of bytes. That said, each line ends in a pair of bytes (CRLF) - 0x0D 0x0A. You can use those as a delimiter to tell where the end of a word is.

Once you've loaded a block into memory, you can use those CRLF sequences to indicate the next word. You could push these into an array, or build an index table for the block, so you can then randomly choose one.

[zellie]

my program is sequentially reading the words in my file. So everytime I run my program, it always starts with the same word. (ofcourse the rest of words are the same too).
Is it there any way where everytime I run my program the sequence of words changes?

[Gizmo]

You'll have to implement a random number generator in order to do that. There are a lot of implementations of random numbers in assembly out on the 'net; This one is an implementation of the classic Knuth random number generator, which is fine for most applications. Be aware, though, that the classic Knuth implementation has a distribution in the least significant bit of EXACTLY 50% (or so I've read). This makes it unsuitable for some applications, thought it should work fine for you.