DSRA#1CTSA#2DTRA#3VCC4RTSA#5INTA6CSA#7TXA8IOW#9TXB10CSB#11INTB12RTSB#13GND14DTRB#15CTSB#16DSRB#17CDB#18RIB#19RXB20CLKSEL21A222A123A024XTAL125XTAL226RESET27GND28RXC29RIC#30CDC#31DSRC#32CTSC#33DTRC#34VCC35RTSC#36INTC37CSC#38TXC39IOR#40TXD41CSD#42INTD43RTSD#44GND45DTRD#46CTSD#47DSRD#48CDD#49RID#50RXD51VCC52D053D154D255D356D457D558D659D760GND61RXA62RIA#63CDA#64