Slide Show



Stewart Stallworthy,

Rickmansworth,

Hertfordshire.



This routine can be used to Poke to the screen any pre-

defined picture or pictures. Whilst a Basic program would

take approximately 60 seconds, this routine takes less than

one second, and can therefore be usefully incorporated in

Basic programs. First draw a picture on the screen, then

save it on tape -

        SAVE "Picture" SCREEN$

The next step is to load the picture bytes into memory.

The routine is written to look for them at memory address

40100.

        CLEAR 39997

        LOAD "Slide" CODE 40000,48

        LOAD "Picture" CODE 40100,6912

Now type

        RANDOMIZE USR 40000

and all should be revealed. Each picture takes 6912 bytes,

and additional pictures may be located at other memory

addresses, for example 47013 and 53926. If these are used,

it will be necessary to make the routine look at the

correct starting address, and this is done as follows. For

picture starting at memory address 47013,

        POKE 40008,165

        POKE 40009,183

For picture starting at memory address 53926,

        POKE 40008,166

        POKE 40009,210