 Certain 65XE and 800XE machines sold in Eastern Europe had a buggy GTIA chip, specifically those machines made in China in 1991.The third custom support chip, named POKEY, is responsible for reading the keyboard, generating sound and serial communications (in conjunction with the PIA chip (Peripheral Interface Adapter, 6520) commands and IRQs, plus controlling the 4 joystick movements on 400/800 and later RAM banks and/or ROM(OS/BASIC/Self-test) enables for XL/XE lines).It also provides timers, a random number generator (for generating acoustic noise as well as random numbers), and maskable interrupts.