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leave stack at zero; to not do FALSE R15 because it is zero on start

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Dmitry Petukhov 2019-10-12 02:27:58 +05:00
parent c9232a21c7
commit d21dc971d1
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GPG Key ID: 2301D26BDC15160D
2 changed files with 34 additions and 15 deletions
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34
stage0/stage0_monitor.hex0
View File

@ -21,9 +21,19 @@
# ;; Prepare often-used values that will be held in registers
090001AC # ABS R10 R12 ; Set R10 to 1
E0002D2B1100 # LOADUI R11 0x1100 ; R11 will hold 0x1100
090004DB # COPY R13 R11 ; Stack will start at 0x1100
# ;; R14 will be storing our condition
0D00002F # FALSE R15 ; Our holder
#
# ;; R14 will be storing our condition
# ;;
# ;; R13 will be a stack pointer. It will be zero
# ;; on the start, and the stack grows up.
# ;; This means that when stack is used, the
# ;; first instructions of this program will be
# ;; overwritten. But because this is initialization
# ;; code, it is already not used at the time.
# ;; And the stack usage is fixed - there is only one CALL
# ;; instruction in this file
# ;;
# ;; R15 Is our holder. It is initialized to zero on start.
# ;; Prep TAPE_01
0900040B # COPY R0 R11 ; 0x1100
@ -33,7 +43,7 @@ E0002D2B1100 # LOADUI R11 0x1100 ; R11 will hold 0x1100
050210BA # OR R0 R11 R10 ; 0x1101
42100001 # FOPEN_WRITE
# :loop ; offset = 26
# :loop ; offset = 1e
0D000021 # FALSE R1 ; Read from tty
42100100 # FGETC ; Read a Char
E000A030000d # CMPSKIPI.NE R0 13 ; Replace all CR
@ -67,7 +77,7 @@ E100B0F0000f # ANDI R15 R0 0x0F ; Store First nibble
# ;; Combined second nybble in pair with first
# :second_nybble ; offset = 76
# :second_nybble ; offset = 6e
E0002D5F0004 # SL0I R15 4 ; Shift our first nibble
E100B000000f # ANDI R0 R0 0x0F ; Mask out top
0500000F # ADD R0 R0 R15 ; Combine nibbles
@ -80,7 +90,7 @@ E100B000000f # ANDI R0 R0 0x0F ; Mask out top
42100200 # FPUTC
3C00ff90 # JUMP @loop ; Try to get more bytes
# :hex ; offset = 96
# :hex ; offset = 8e
# ;; Deal with line comments starting with #
E1001FE00023 # CMPUI R14 R0 35
@ -117,23 +127,23 @@ E0002C7E000e # JUMP.LE R14 @ascii_low
# ;; Ignore the rest
3C00001e # JUMP @ascii_other
# :ascii_num ; offset = fa
# :ascii_num ; offset = f2
E10011000030 # SUBUI R0 R0 48
0D01001D # RET R13
# :ascii_low ; offset = 104
# :ascii_low ; offset = fc
E10011000057 # SUBUI R0 R0 87
0D01001D # RET R13
# :ascii_high ; offset = 10e
# :ascii_high ; offset = 106
E10011000037 # SUBUI R0 R0 55
0D01001D # RET R13
# :ascii_other ; offset = 118
# :ascii_other ; offset = 110
0D000030 # TRUE R0
0D01001D # RET R13
# :ascii_comment ; offset = 120
# :ascii_comment ; offset = 118
0D000021 # FALSE R1 ; Read from tty
42100100 # FGETC ; Read another char
E000A030000d # CMPSKIPI.NE R0 13 ; Replace all CR
@ -145,7 +155,7 @@ E1001FE0000a # CMPUI R14 R0 10 ; Stop at the end of line
E0002C6Effd4 # JUMP.NE R14 @ascii_comment ; Otherwise keep looping
3C00ffc8 # JUMP @ascii_other
# :finish ; offset = 150
# :finish ; offset = 148
0900040B # COPY R0 R11 ; Close TAPE_01
42100002 # FCLOSE
050210BA # OR R0 R11 R10 ; Close TAPE_02

15
stage0/stage0_monitor.s
View File

@ -21,9 +21,18 @@
ABS R10 R12 ; Set R10 to 1
LOADUI R11 0x1100 ; R11 will hold 0x1100
COPY R13 R11 ; Stack will start at 0x1100
;; R14 will be storing our condition
FALSE R15 ; Our holder
;; R14 will be storing our condition
;;
;; R13 will be a stack pointer. It will be zero
;; on the start, and the stack grows up.
;; This means that when stack is used, the
;; first instructions of this program will be
;; overwritten. But because this is initialization
;; code, it is already not used at the time.
;; And the stack usage is fixed - there is only one CALL
;; instruction in this file
;;
;; R15 Is our holder. It is initialized to zero on start.
;; Prep TAPE_01
COPY R0 R11 ; 0x1100