EUG PD


ASC, VDU, CHR$ Codes

 
Published in EUG #13

Introduction

Hello to all you folk out there!

I hope that now I am 'official' sub-editor of this section, I will be able to provide something of interest for each issue. This must depend on you too. I must have plenty of submissions to help me to keep up a steady flow of material to pass on. I hope that those budding artists and programmers among you will send me some items soon. Any comment, suggestion, idea for a program or anything else which could come under this heading will be welcome.

I hope to be able to produce a write up on any programs I receive as I did for my programs in past issues so any notes you may be able to add will be appreciated.

As I have yet to receive a contribution, for this issue I have only been able to put together some of my own programs which may be helpful to any programmers among you and two graphics screens which Will has passed on to me.

Programs

Some of you may remember the Memory Map programs of EUG #10. These used the expanded character set of an Epson-compatible printer to form a double line frame round each section and single line division within the sections. If you do not get this it may be that your printer has not got the graphics or that the printer coding I have used is not right for your printer so you will need to refer to your printer manual.

These four programs are similar and useful for reference when programming. Though most of this information is given in the manual, and I know some of it sticks in one's memory, I find it useful to keep these in transparent folders in a file - it saves a lot of wear and tear on the manual! Mine is almost falling apart!

While they are almost self-explanatory, here is a summary of these:

ASC, VDU, CHR$ CODES

I have listed these in two groups - control codes and characters. I think this is a clearer listing than in the manual.

Colour Information

Again taken from the manual but handy to have together the other info.

INKEY Negative Values

Probably the most useful one as the response is usually quicker than using GET. Also these values are used in m/code progams. They are listed in alphabetical order as in the manual and also sorted into numerical order. I find this useful when looking for a number which I don't recognise. This does take a little time to set up. Also I have included the Hex numbers as these get used in m/code programs.

Token Values

These can be useful when examing a BASIC program in memory especially when trouble-shooting!

Graphics
Do you remember the film show in EUG #11? This gave give good animation of two screens but was rather slow and jerky on the standard Elk and almost too fast on a Turbo one. I have since written another m/code routine which is simpler and can be even faster! This was soon slowed down by adding a delay loop. This can be varied by entering a value between 1 and 35 into the delay loop and I have added an input routine for doing this. A low value is needed for those without a Turbo board and a higher one with Turbo Mode enabled. Have fun trying this out!

The screens are:

FILMRb. Where Christopher Robin is seen displaying an urgent cry of HELP! from his friend Piglet.

FILMPh. Where Winnie goes a flying somersault!

Simon Pilley has sent several similar screens which have been passed to me and I have chosen the Mode 1 versions as I thought that the added colour enhanced them although Mode 0 would give better definition.

Sorry there are only two. This is because they cannot be compressed very much and take up a lot of precious disk space. I hope to have something more to say on the subject of Screen Compression later.

I hope that I shall have something more interesting for EUG #14.

That's it for now. Hoping to hear from you!!

Richard Dimond, EUG #13

Richard Dimond