Initial commit: floating bus test

- Translated "Have an Apple Split" routine to assembly.
- Created build script to build autorunning floatbus.dsk disk image.

.gitignore

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+*.o
+floatbus/floatbus.dsk

floatbus/apple_split_1.asm

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+;;; Assembly conversion of listings 1 and 2 from
+;;; http://rich12345.tripod.com/aiivideo/softalk.html#list2
+
+	!convtab <apple ii/convtab.bin>
+	!to "apple_split_1.o", plain
+	* = $6000
+
+	V2 = $2D 		; bottom point for vertical line drawing
+	HOME = $FC58
+	SETCOL = $F864
+	VLINE = $F828
+	MSGPOS = $690
+main:
+
+;;; 100 HOME
+	JSR HOME
+	
+;;; 200 FOR K = 0 TO 39
+	LDX #39
+loop:	
+;;; 210 POKE 1448 + K, 14 * 16
+	LDA #$E0
+	STA 0x5a8,X
+;;; 220 POKE 2000 + K, 10 * 16
+	LDA #$A0
+	STA 0x7D0,X
+
+	TXA
+	TAY
+
+;;; 230 COLOR= K + 4
+	ADC #4
+	JSR SETCOL
+
+;;; 240 VLIN 25,45 AT K
+	LDA #45
+	STA V2
+	LDA #25
+	JSR VLINE
+	
+;;; 250 NEXT K
+	DEX
+	BPL loop
+
+;;; 300 VTAB 6: HTAB 17
+;;; 310 PRINT "APPLE II"
+
+	LDX #7
+msgloop:	
+	LDA message,X
+	STA MSGPOS,X
+	DEX
+	BPL msgloop
+
+;;; 400 CALL 768
+;;; 500 GOTO 400
+
+
+forever:
+	jsr sync
+	jmp forever
+
+message:	!text "APPLE II"
+sync:	
+	STA $C052
+	LDA #$E0
+loop1:
+	LDX #$04
+loop2:	
+	CMP $C051
+	BNE loop1
+	DEX
+	BNE loop2
+	LDA #$A0
+loop3:	
+	LDX #$04
+loop4:	
+	CMP $C050
+	BNE loop3
+	DEX
+	BNE loop4
+	STA $C051
+	RTS

floatbus/apple_split_1.bas

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+10 H$ = "300:8D 52 C0 A9 E0 A2 04 CD 51 C0 D0 F9 CA D0 F8 A9 A0 A2 04 CD 50 C0 D0 F9 CA D0 F8 8D 51 C0 60 N D9C6G"
+20 FOR X = 1 TO LEN(H$): POKE 511 + X, ASC ( MID$ (H$,X,1)) + 128: NEXT
+30 POKE 72,0: CALL -144
+100 HOME
+200 FOR K = 0 TO 39
+210 POKE 1448 + K, 14 * 16
+220 POKE 2000 + K, 10 * 16
+230 COLOR= K + 4
+240 VLIN 25,45 AT K
+250 NEXT K
+300 VTAB 6: HTAB 17
+310 PRINT "APPLE II"
+400 CALL 768
+500 GOTO 400

floatbus/build

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+#!/usr/bin/env bash
+set -euo pipefail
+set -x
+export ACME="$HOME/gh/acme/ACME_Lib"
+cp ../dsk/blank.dsk floatbus.dsk
+acme apple_split_1.asm
+applecommander -d floatbus.dsk HELLO || echo '(No HELLO to delete)'
+applecommander -d floatbus.dsk BHELLO || echo '(No HELLO to delete)'
+applecommander -p floatbus.dsk HELLO A < hello.bas.bin
+applecommander -p floatbus.dsk BHELLO B 0x6000 < apple_split_1.o

shasum/shasum.a

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+	!to "shasum.o", plain
+	* = $6000
+	jmp test
+
+	;; clear addresses:
+	;; (http://apple2.org.za/gswv/a2zine/faqs/csa2pfaq.html#017)
+	;; 06-09
+	;; EB-EF
+	;; FA-FD
+	
+	!addr	src = $06
+	!addr	dest = $08
+	!addr   input = $eb
+	
+h0:	!32 0			; return value (hash)
+h1:	!32 0
+h2:	!32 0
+h3:	!32 0
+h4:	!32 0
+ml:	!32 0			; message length
+w:	!fill 64, 0
+w_next:	!fill 64, 0
+kh0:	!be32 $67452301		; initial values for h0..h4
+kh1:	!be32 $EFCDAB89
+kh2:	!be32 $98BADCFE
+kh3:	!be32 $10325476
+kh4:	!be32 $C3D2E1F0
+k1:	!be32 $5A827999		; k = constants
+k2:	!be32 $6ED9EBA1
+k3:	!be32 $8F1BBCDC
+k4:	!be32 $CA62C1D6	
+test:	jsr $ff2d
+	rts
+
+	!eof
+
+TODOs
+[ ] Routine to print n hex bytes (address, length (byte))
+[ ] Routine to get the next 16 values (64 bytes)
+[ ] Routine to get w[i] one i at a time, and rebuild next 16 values
+[ ] Routine to get the next 16 values (64 bytes) of input
+
+Chacha20 code isn't so useful, because it's little-endian.
+
+611B ADD32
+612B XOR32
+613A ROL16
+6152 RORX
+6165 ROL12
+616E ROL8
+6180 ROL7
+6189 PR32
+
+Needed sha1sum:
+- leftrotate 1  --> ?
+- leftrotate 5  --> ROL8, RORX 3
+- leftrotate 30 --> RORX 2
+