1                                	.sbttl	M9312 'ZZ' BOOT prom diagnostic tests
       2                                
       3                                	; This boot PROM is not a real boot PROM, but a pseudo-boot device that
       4                                	; runs the internal M9312 full diagnostics continuously, incl memory test.
       5                                	;
       6                                	; This PROM is intimately tied to the standard 23-248F1 console/diag PROM,
       7                                	; and will NOT work in boards other than a real M9312 with a '248F1.
       8                                	;
       9                                	; Standard devices are 82S131, Am27S13, 74S571 or other compatible bipolar
      10                                	; PROMs with a 512x4 TriState 16pin DIP architecture. This code resides in
      11                                	; the low half of the device; the top half is blank and unused.
      12                                	;
      13                                	; Alternatively, 82S129 compatible 256x4 TriState 16pin DIP devices can be
      14                                	; used, as the uppermost address line (hardwired low) is an active low chip
      15                                	; select (and will be correctly asserted low).
      16                                
      17 165564                         diags	=165564				; ph2 diags, ret to 2(R4), temp R2,R3,R5,SP
      18 165430                         prtoct	=165430				; print octal in R0, ret to 2(R1), temp R2,R3
      19 165500                         prteol	=165500				; print EOL, ret to 2(R1), temp R2,R3
      20 165540                         txchar	=165540				; print char in R2, ret to 2(R3)
      21                                
      22                                	.asect
      23 173000                         	.=173000
      24                                
      25                                	; --------------------------------------------------
      26                                
      27 173000    132     132          start:	.ascii	"ZZ"			; device code (reversed)
      28                                
      29 173002 000176                  	.word	last-.			; offset to next boot header
      30                                
      31 173004 000261                  zz0n:	sec				; boot std csr, unit zero, no diags
      32 173006 012700  000000          zz0d:	mov	#0,r0			; boot std csr, unit zero, with diags [NOTUSED]
      33 173012 012701  000000          zzNr:	mov	#0,r1			; boot std csr, unit <R0> [NOTUSED]
      34 173016 010704                  zzNb:	mov	pc,r4			; boot csr <R1>, unit <R0>
      35 173020 103064                  	bcc	diag			; br if diags requested
      36 173022 000402                  	br	go			; return to (R4)+2 from diags
      37                                					; then skip over pseudo reboot vector
      38                                
      39                                	; --------------------------------------------------
      40                                
      41 173024 173000                  	.word	173000			; prom start addess @ 24
      42 173026 000340                  	.word	340			; and priority level @ 26
      43                                
      44                                	; --------------------------------------------------
      45                                
      46 173030 010701                  go:	mov	pc,r1			; setup return address
      47 173032 000455                  	br	87$			; call EOL print
      48                                
      49 173034 005003                  2$:	clr	r3			; R3=000000 C=0
      50 173036 005203                  	inc	r3			; R3=000001 C=0
      51 173040 005103                  	com	r3			; R3=177776 C=1
      52 173042 006203                  	asr	r3			; R3=177777 C=0
      53 173044 006303                  	asl	r3			; R3=177776 C=1
      54 173046 006003                  	ror	r3			; R3=177777 C=0
      55 173050 005703                  	tst	r3			; R3=177777 C=0
      56 173052 005403                  	neg	r3			; R3=000001 C=1
      57 173054 005303                  	dec	r3			; R3=000000 C=1
      58 173056 005603                  	sbc	r3			; R3=177777 C=1
      59 173060 006103                  	rol	r3			; R3=177777 C=1
      60 173062 005503                  	adc	r3			; R3=000000 C=1
      61 173064 000303                  	swab	r3			; R3=000000 C=0
      62 173066 001377                  	bne	.			; br . if FAIL
      63                                
      64 173070 010704                  	mov	pc,r4			; setup return address
      65 173072 000437                  	br	diag			; call ph2 diagnostics
      66                                
      67 173074 005200                  	inc	r0			; bump pass count
      68 173076 010001                  	mov	r0,r1			;
      69 173100 010102                  	mov	r1,r2			; check some registers
      70 173102 010203                  	mov	r2,r3			;
      71 173104 010304                  	mov	r3,r4			;
      72 173106 010405                  	mov	r4,r5			; save pass count
      73                                
      74 173110 010701                  	mov	pc,r1			; where we are
      75 173112 062701  000032          	add	#30$-.,r1		; offset to string
      76 173116 112102                  4$:	movb	(r1)+,r2		; get next char
      77 173120 001403                  	beq	5$			; br if done
      78 173122 010703                  	mov	pc,r3			; setup return address
      79 173124 000414                  	br	85$			; print char in R2
      80 173126 000773                  	br	4$			; loop
      81                                
      82 173130 010701                  5$:	mov	pc,r1			; setup return address
      83 173132 000413                  	br	86$			; call octal print of R0
      84                                
      85 173134 010701                  	mov	pc,r1			; setup return address
      86 173136 000413                  	br	87$			; call EOL print
      87                                
      88 173140 010500                  	mov	r5,r0			; restore pass count
      89 173142 000734                  	br	2$			; and loop forever
      90                                
      91                                	; --------------------------------------------------
      92                                
      93 173144    105     156     144  30$:	.asciz	"End Pass "		; a message
         173147    040     120     141  
         173152    163     163     040  
         173155    000                  
      94                                
      95 173156 000137  165540          85$:	jmp	@#txchar		; jump to char print
      96 173162 000137  165430          86$:	jmp	@#prtoct		; jump to octal print
      97 173166 000137  165500          87$:	jmp	@#prteol		; jump to EOL print
      98 173172 000137  165564          diag:	jmp	@#diags			; jump to console diags
      99                                
     100                                	; --------------------------------------------------
     101                                
     102 173176                         	.=start+176
     103 173176 152737                  crc16:	.word	<152737>		; CRC-16 will go here
     104                                
     105                                last:	; next boot prom starts here
     106                                
     107                                	.end
     107