1 8080 MACRO ASSEMBLER, VER 3.0 ERRORS = 0 + 07:34 07/16/2019 + PAGE 1 0000 ORG 0 ; ; 2SIO LOADER FOR ALTAIR BASIC ; ; ** FOR VERSIONS < 4.0 SET SENSE SWITCHES A11, A10 ON ** ; ** FOR VERSIONS >= 4.0 SET SENSE SWITCHES OFF ** ; 0000 3E03 MVI A,3 ;RESET THEN INIT ACIA 0002 D310 OUT 010H 0004 3E15 MVI A,015H ;015H FOR 8N1, 011H FOR 8N2 0006 D310 OUT 010H ; H = MSB OF LOAD ADDRESS ; L = LSB OF LOAD ADDRESS = LENGTH OF LOADER = LEADER BYTE ; LXI H,00F7DH ;4K BASIC V3.0 ; LXI H,00FAEH ;4K BASIC V3.2 ; LXI H,00FC2H ;4K BASIC V4.0 ; LXI H,01F7DH ;8K BASIC V3.0, V3.1 ; LXI H,01FAEH ;8K BASIC V3.2 ; LXI H,01FC2H ;8K BASIC V4.0 0008 21AE2F LXI H,02FAEH ;EXTENDED BASIC V3.2 ; LXI H,03FC2H ;EXTENDED BASIC V4.0, V4.1 ; LXI H,07EC2H ;EXTENDED DISK BASIC V5.0 000B 311A00 LOOP: LXI SP,STACK ;INIT SP SO A RET JUMPS TO LOOP 000E DB10 IN 010H ;GET 2SIO STATUS 0010 0F RRC ;NEW BYTE AVAILABLE? 0011 D0 RNC ;NO (JUMPS BACK TO LOOP) 0012 DB11 IN 011H ;GET THE BYTE 0014 BD CMP L ;NEW BYTE = LEADER BYTE? 0015 C8 RZ ;YES (JUMPS BACK TO LOOP) 0016 2D DCR L ;NOT LEADER, DECREMENT ADDRESS 0017 77 MOV M,A ;STORE THE BYTE (REVERSE ORDER) 0018 C0 RNZ ;LOOP UNTIL L = 0 0019 E9 PCHL ;JUMP TO CODE JUST DOWNLOADED 001A 0B00 STACK: DW LOOP END NO PROGRAM ERRORS 1 8080 MACRO ASSEMBLER, VER 3.0 ERRORS = 0 + 07:34 07/16/2019 + PAGE 2 SYMBOL TABLE * 01 A 0007 B 0000 C 0001 D 0002 E 0003 H 0004 L 0005 LOOP 000B M 0006 PSW 0006 SP 0006 STACK 001A