Running programs on the Model A
The programs in this book and on the cassette are supplied as versions that take advantage of the high-resolution graphics capabilities of the BBC Microcomputer Model B. Although on the Model A there will be lower resolution and fewer colours, Model A users will lose very little in terms of overall effect. The following instructions show how to alter the programs so they will run on the Model A.
All but two of the programs in this book will run on the Model A if the MODE statement at the beginning of the program we, changed to MODE 5. The procedure is as follows:
Modifications for FIELD and ISLAND
FIELD and ISLAND require further modification as listed below.
FIELD
Change line 20 to read MODE 5
Change line 150 to read VDU 28,0,9,19,0
Change line 190 to read VDU 28,0,9,19,0
Change line 350 to read VDU 28,0,31,19,10
ISLAND
Change line 20 to read MODE 5.
Delete lines go and 150 from the program. The way to do this is to type at the end of the listing:
90 (RETURN)
150 (RETURN)
When you LIST the program you will see that lines 90 and 150 have been removed.
PROCSURF, the procedure giving the effect of white surf on the waves, will not operate on the Model A.