I thought it would be better to separate the procedure to paint white and the procedure to paint black. Points listed below.

• I was misunderstanding the size of screen memory
• I could not use expressions such as R0 and R1
• M[0] stores the screen state
• M[1] stores the screen memory index
• If it is in the same state as before, it ends
• I described branch processing when the value of keyboard memory (M [24576]) is 0

I am unfamiliar so I can not write repetitive processing immediately.