400 ORG 256 ;START IN PAGE 1 ; ; INITIALIZE SECOND PORT OF 2-SIO CARD ; 400 076 SBOOT: MVI A,URESET ;CLEAR M6850 UART 003 402 323 OUT SIO1 022 ; 404 076 MVI A,U8D1SN ;8 DATA, 1 STOP, NO PARITY 025 406 323 OUT SIO1 022 ; 410 041 ABOOT: LXI H,0 ;[H,L]=>LOAD ADDRESS 000 000 413 016 MVI C,128 ;[C]=LOAD COUNTER 200 ; 415 333 APEIN: IN SIO1 ;CHARACTER FROM APE? 022 417 346 ANI RXRDY 001 421 312 JZ APEIN ;NO - TRY AGAIN 015 001 424 333 IN SIO1+1 ;YES - SAVE IT 023 426 167 MOV M,A 427 043 INX H ;INCREMENT LOAD ADDRESS 430 015 DCR C ;DECREMENT LOAD COUNT 431 302 JNZ APEIN ;DONE? NO - CONTINUE 015 001 ; 434 303 JMP 0 ;START COLD BOOT LOADER AT 0 000 000 ; 437 END SBOOT