Screen does not start at 0 so your poke won't place anyhing on screen (actually, address 0 is the PORT register on the 6510 iirc).
POKE X CHR$(209) is not valid syntax, POKE takes a memory address (in decimal) a COMMA and the value (0-FF) in decimal.
Also.. CHR$ converts an ascii value to a character.. you don't want that here..
Also.. the character color has not been set under the ball, so it won't show up on most of the screen-area..
Screen memory starts at 1024, color memory at 55296 so to show your ball, you'll do
POKE 1024,209
POKE 55296,1
Also, you should use 81 and not 209, since the machine is in uppercase mode, and 209 is the inverted circle in that mode.
Why spend the time to write an article with examples that do not actually work?
POKE X CHR$(209) is not valid syntax, POKE takes a memory address (in decimal) a COMMA and the value (0-FF) in decimal.
Also.. CHR$ converts an ascii value to a character.. you don't want that here..
Also.. the character color has not been set under the ball, so it won't show up on most of the screen-area..
Screen memory starts at 1024, color memory at 55296 so to show your ball, you'll do
POKE 1024,209 POKE 55296,1
Also, you should use 81 and not 209, since the machine is in uppercase mode, and 209 is the inverted circle in that mode.
Why spend the time to write an article with examples that do not actually work?