Gniazdo SIO
From Atariki
Serial I/O (SIO) Port (all machines): 2 12 o o o o o o o o o o o o o 1 13 1. Clock Input 8. Motor Control 2. Clock Output 9. Proceed 3. Data Input 10. +5V/Ready (not on 1200XL) 4. Ground 11. Audio Input 5. Data Output 12. +12V (400,800 only. 1400XL/1450XLD?) 6. Ground 13. Interrupt 7. Command