Department of Computer Science and Information EngineeringNational Cheng Kung University, TAIWAN
HANELFigure 15-8. 8031 Connection to External Program ROM and the 8255PROGRAMMING THE 82558031 System With 8255
(cont’)
74LS373
AD7 AD08255A0 D7 D0
RDWR A12 A8G D Q OC
A7Vcc(^2864) (2764) 8Kx8programROM
A12
P3.7EAP3.6PSENP2.7 P2.0ALE P0.7 P0.0
CS A1A0
WRRD PA PB PC RES
A12A8 A7 A0 D7
Vpp D0
CE
OE