mirror of https://github.com/Klaus2m5/VTL02.git
Speedy Gonzales update 3
merged oper: and exec: added braces as shift operator added check for ctrl-c and ctrl-z to goto to allow user to escape from an unintentional loop
This commit is contained in:
Klaus2m5
parent
fbd001c897
commit
217281b671
436
vtl02sg.a65
436
vtl02sg.a65
|
|
@ -167,31 +167,23 @@
|
|||
; programming principles remained at low priority.
|
||||
;
|
||||
; VTL02 for the 2m5 emulated 6502 SBC
|
||||
; - released: 20-nov-2015
|
||||
; - codename: speedy Gonzales
|
||||
; - based on VTL02C, changes by Klaus2m5
|
||||
;
|
||||
; added a timer variable {/} with 10ms increments
|
||||
; required atomic variable fetch & store.
|
||||
; replaced some jsr calls with inline code
|
||||
; for skpbyte:, getbyte:, plus:, minus:.
|
||||
; replaced cvbin calls to mul: & plus: with custom
|
||||
; inline multiply by 10 & digit adder.
|
||||
; removed simulation from startup of eval:.
|
||||
; mainloop uses inline code to advance to next
|
||||
; sequential program line.
|
||||
; find: is now only used for true branches.
|
||||
; added a timer variable {/} with 10ms increments.
|
||||
;
|
||||
; added braces as shift operators.
|
||||
; A}B shifts A by B bits to the right.
|
||||
; A{B shifts A by B bits to the left.
|
||||
; result is unpredictable if B > 16
|
||||
;
|
||||
; added a statement delimiter {;} allowing multi
|
||||
; statement lines.
|
||||
; branch to same line is now allowed.
|
||||
; {?="..."} & unmatched {)} (used for comments) can
|
||||
; not be continued.
|
||||
; added decimal to binary conversion on line entry
|
||||
; avoiding the runtime conversion.
|
||||
; abbreviated getting a simple variable in getval:.
|
||||
; bypassed setting a simple variable in exec:.
|
||||
; added inline divide by 10 to prnum:.
|
||||
; fixed statement delimiter not overriding mismatched
|
||||
; parentheses.
|
||||
;
|
||||
; line numbers >= 65280 are now reserved for the
|
||||
; following fast return & goto features.
|
||||
; added a gosub stack, depth = 16 address words.
|
||||
|
|
@ -206,6 +198,45 @@
|
|||
; character in the allowed range preceeds the line
|
||||
; number.
|
||||
;
|
||||
; example (prints the first 1000 prime numbers):
|
||||
; 10 /=0;Q=d;V=5;U=25;X=1000
|
||||
; 20 N=2;==b
|
||||
; 30 N=N+1;==b
|
||||
; 40 N=N+2;==b
|
||||
; a100 N=N+2;==b
|
||||
; 120 N=N+4;==b
|
||||
; 150 #=a
|
||||
; b200 #=N<U[Q;Q=c;V=V+2;U=V*V
|
||||
; c300 D=5
|
||||
; e310 A=N/D;#=%]=;D=D+2;#=D>V[d
|
||||
; 320 A=N/D;#=%]=;D=D+4;#=D<V[e
|
||||
; d400 ?=N;?=""
|
||||
; 420 X=X-1;#=X[=
|
||||
; 435 ?="Execution time: ";
|
||||
; 445 ?=//100;$=46;#=%>10[465;?=0
|
||||
; 465 ?=%;?=" seconds"
|
||||
;
|
||||
; internal changes:
|
||||
; added required atomic variable fetch & store.
|
||||
; replaced some jsr calls with inline code
|
||||
; for skpbyte:, getbyte:, plus:, minus:.
|
||||
; replaced cvbin calls to mul: & plus: with custom
|
||||
; inline multiply by 10 & digit adder.
|
||||
; removed simulation from startup of eval:.
|
||||
; mainloop uses inline code to advance to next
|
||||
; sequential program line.
|
||||
; find: is now only used for true branches.
|
||||
; added decimal to binary conversion on line entry
|
||||
; avoiding the runtime conversion.
|
||||
; abbreviated getting a simple variable in getval:.
|
||||
; bypassed setting a simple variable in exec:.
|
||||
; added inline divide by 10 to prnum:.
|
||||
; fixed statement delimiter not overriding mismatched
|
||||
; parentheses.
|
||||
; merged oper: into getval: and progr: into exec:
|
||||
; added a check for ctrl-c & ctrl-z during goto to
|
||||
; allow user escape from a loop.
|
||||
;
|
||||
;-----------------------------------------------------;
|
||||
; VTL02C variables occupy RAM addresses $0080 to $00ff,
|
||||
; and are little-endian, in the 6502 tradition.
|
||||
|
|
@ -223,15 +254,13 @@ at = $80 ; {@}* internal pointer / mem byte
|
|||
; VTL02C standard user variable space
|
||||
; {A B C .. X Y Z [ \ ] ^ _}
|
||||
; VTL02C system variable space
|
||||
space = $c0 ; { }* gosub stack /
|
||||
; Starting with VTL02B:
|
||||
; the space character is no
|
||||
; longer a valid user variable
|
||||
; nor a "valid" binary operator.
|
||||
; It is now only significant as a
|
||||
; numeric constant terminator and
|
||||
; as a place-holder in strings
|
||||
; and program listings.
|
||||
space = $c0 ; { }* gosub & return stack pointer
|
||||
; Starting with VTL02B:
|
||||
; the space character is no longer a valid user
|
||||
; variable nor a "valid" binary operator. It is
|
||||
; now only significant as a numeric constant
|
||||
; terminator and as a place-holder in strings
|
||||
; and program listings.
|
||||
bang = $c2 ; {!} return line number
|
||||
quote = $c4 ; {"} user ml subroutine vector
|
||||
pound = $c6 ; {#} current line number
|
||||
|
|
@ -239,17 +268,18 @@ dolr = $c8 ; {$}* temp storage / char i/o
|
|||
remn = $ca ; {%} remainder of last division
|
||||
ampr = $cc ; {&} pointer to start of array
|
||||
tick = $ce ; {'} pseudo-random number
|
||||
lparen = $d0 ; {(}* old line # / begin sub-exp
|
||||
lparen = $d0 ; {(}* temp line # / begin sub-exp
|
||||
rparen = $d2 ; {)}* temp storage / end sub-exp
|
||||
star = $d4 ; {*} pointer to end of free mem
|
||||
; $d6 ; {+ , - .} valid variables
|
||||
; (1) $fe ; {/} 10ms count up timer
|
||||
; Interpreter argument stack space
|
||||
arg = $e0 ; {0 1 2 3 4 5 6 7 8 9 :}*
|
||||
arg = $e0 ; {0 1 2 3 4 5 6 7 8 9}*
|
||||
; Rarely used variables and argument stack overflow
|
||||
; = $f4 ; {:}* array variable header
|
||||
semico = $f6 ; {;}* statement delimiter
|
||||
lthan = $f8 ; {<}* user memory byte pointer
|
||||
equal = $fa ; {=}* temp / gosub & return addr.
|
||||
equal = $fa ; {=}* temp / gosub & return stack
|
||||
gthan = $fc ; {>}* temp / call ML subroutine
|
||||
ques = $fe ; {?}* temp / terminal i/o
|
||||
;
|
||||
|
|
@ -275,11 +305,10 @@ timr_adr = timr_var*2|$80
|
|||
ESC = 27 ; "Cancel current input line" key
|
||||
BS = 8 ; "Delete last keypress" key
|
||||
OP_OR = '|' ; Bit-wise OR operator
|
||||
timr_var = '/' ; 10 ms count up variable
|
||||
lblary = $0100 ; array with goto labels
|
||||
vtlstck = $0140 ; gosub stack space, 64 bytes
|
||||
linbuf = $0200 ; input line buffer
|
||||
prgm = $0400 ; VTL02C program grows from here
|
||||
prgm = $0280 ; VTL02C program grows from here
|
||||
himem = $7800 ; ... up to the top of user RAM
|
||||
vtl02c = $f800 ; interpreter cold entry point
|
||||
; (warm entry point is startok)
|
||||
|
|
@ -293,7 +322,7 @@ diag = io_area+$fc ;diag reg, bit 7 = exit to mon
|
|||
org vtl02c
|
||||
;-----------------------------------------------------;
|
||||
; Initialize program area pointers and start VTL02C
|
||||
; 17 bytes
|
||||
;
|
||||
lda #lo(prgm)
|
||||
sta ampr ; {&} -> empty program
|
||||
lda #hi(prgm)
|
||||
|
|
@ -327,8 +356,8 @@ start:
|
|||
jsr outnl
|
||||
user:
|
||||
lda #0 ; last line # = direct mode
|
||||
sta lparen
|
||||
sta lparen+1
|
||||
sta pound
|
||||
sta pound+1
|
||||
jsr inln ; input a line from the user
|
||||
lda linbuf ; check for line label char
|
||||
cmp #$60
|
||||
|
|
@ -339,6 +368,7 @@ user1:
|
|||
jsr cvbin ; skip line number if exists
|
||||
jsr d2b ; convert numbers in line to binary
|
||||
bne stmnt ; no: execute direct statement
|
||||
; populate the acronym label array
|
||||
lda lblary+62 ; label array populated ?
|
||||
bne user2 ; yes: skip polpulating it
|
||||
tya ; no: populate now!
|
||||
|
|
@ -380,10 +410,10 @@ ldaray3:
|
|||
pla
|
||||
tay
|
||||
user2:
|
||||
jmp exec
|
||||
jmp exec ; execute a direct mode statement
|
||||
; - - - - - - - - - - - - - - - - - - - - - - - - - - ;
|
||||
; Delete/insert/replace program line or list program
|
||||
; 7 bytes
|
||||
;
|
||||
stmnt:
|
||||
clc
|
||||
lda pound
|
||||
|
|
@ -394,7 +424,7 @@ stmnt:
|
|||
; entry: Carry must be clear
|
||||
; uses: findln:, outch:, prnum:, prstr:, {@ ( )}
|
||||
; exit: to command line via findln:
|
||||
; 20 bytes
|
||||
;
|
||||
list_:
|
||||
jsr findln ; find program line >= {#}
|
||||
ldx #0
|
||||
|
|
@ -423,7 +453,7 @@ clr_ls:
|
|||
; command prompt (no "OK" means success)
|
||||
; entry: Carry must be clear
|
||||
; uses: find:, start:, linbuf, {@ > # & * (}
|
||||
; 151 bytes
|
||||
;
|
||||
skp2:
|
||||
tya ; save linbuf offset pointer
|
||||
pha
|
||||
|
|
@ -606,13 +636,8 @@ prmsg1:
|
|||
prmsg2:
|
||||
tax ; save closing delimiter
|
||||
jsr inkey ; any key = pause/resume?
|
||||
; patch - remove garbage output when halting print
|
||||
; bcc prout ; no: proceed
|
||||
; jsr inch ; yes: wait for another key
|
||||
;prout:
|
||||
txa ; retrieve closing delimiter
|
||||
beq outnl ; always \n after null delimiter
|
||||
; jsr skpbyte ; skip over the delimiter
|
||||
pro_skp: ; inline skpbyte
|
||||
iny
|
||||
lda (at),y
|
||||
|
|
@ -626,7 +651,8 @@ outnl:
|
|||
lda #$0d ; \n to terminal
|
||||
jmp outch
|
||||
;-----------------------------------------------------;
|
||||
; Execute a (hopefully) valid VTL02C statement at @[y]
|
||||
; Execute (hopefully) valid VTL02C statements at @[y]
|
||||
; exec: will continue until drop to direct mode
|
||||
; entry: @[y] -> left-side of statement
|
||||
; uses: nearly everything
|
||||
; exit: note to machine language subroutine {>=...}
|
||||
|
|
@ -639,18 +665,12 @@ outnl:
|
|||
; operator, the statement will execute as {?="...},
|
||||
; regardless of the variable named on the left side
|
||||
;
|
||||
;execrts1:
|
||||
; rts
|
||||
exec:
|
||||
; jsr getbyte ; fetch left-side variable name
|
||||
; beq execrts ; do nothing with a null statement
|
||||
; cmp #')' ; same for a full-line comment
|
||||
; beq execrts
|
||||
; iny
|
||||
lda (at),y ; inline getbyte
|
||||
beq execend1 ; do nothing with a null statement
|
||||
cmp #')' ; same for a full-line comment
|
||||
beq execend1
|
||||
; the code below allows (N+1) instead of (N=N+1)
|
||||
; sty dolr+1 ; save index if arg[{1}] = arg[{0}]
|
||||
iny
|
||||
cmp #' ' ; is space?
|
||||
|
|
@ -695,8 +715,8 @@ execend:
|
|||
cmp #';' ; statement delimiter ?
|
||||
beq exec ; continue with next statement
|
||||
execend1:
|
||||
lda lparen ; direct mode ?
|
||||
ora lparen+1
|
||||
lda pound ; direct mode ?
|
||||
ora pound+1
|
||||
beq jstart4
|
||||
prog_nxt:
|
||||
ldy #3 ; point {@} to next line address
|
||||
|
|
@ -717,11 +737,9 @@ prg_n2: ; (cc)
|
|||
sta at
|
||||
ldy #1
|
||||
lda (at),y
|
||||
sta lparen ; {(} = {#} = current line number
|
||||
sta pound
|
||||
sta pound ; {#} = current line number
|
||||
iny
|
||||
lda (at),y
|
||||
sta lparen+1
|
||||
sta pound+1
|
||||
ldy #4
|
||||
jmp exec ; loop next line
|
||||
|
|
@ -733,8 +751,6 @@ jstart4:
|
|||
exec_byp:
|
||||
ldx #arg ; initialize argument pointer
|
||||
jsr convp ; arg[{0}] -> left-side variable
|
||||
; jsr getbyte ; skip over assignment operator
|
||||
; jsr skpbyte ; is right-side a literal string?
|
||||
exec_gb3: ; inline getbyte + skpbyte
|
||||
lda (at),y
|
||||
iny ; skip space +1
|
||||
|
|
@ -782,8 +798,8 @@ exec2:
|
|||
jmp execend1
|
||||
|
||||
gosub:
|
||||
lda lparen ; is direct mode ?
|
||||
ora lparen+1
|
||||
lda pound ; is direct mode ?
|
||||
ora pound+1
|
||||
beq gosub3 ; return to commandline
|
||||
lda at ; calculate next line address
|
||||
ldy #3
|
||||
|
|
@ -819,7 +835,6 @@ goto:
|
|||
tax ; save line # low
|
||||
ora arg+3 ; fall through ?
|
||||
bne goto1
|
||||
; sta arg ; invalidate goto {#}
|
||||
jmp execend
|
||||
|
||||
usr:
|
||||
|
|
@ -840,10 +855,14 @@ prnum0:
|
|||
jsr prnum
|
||||
jmp execend
|
||||
|
||||
goto_abort:
|
||||
jsr test_abort ; check for ctrl-c or ctrl-z
|
||||
goto1:
|
||||
lda lparen ; set {!} as return line #
|
||||
lda acia_rx ; allow user abort
|
||||
bne goto_abort
|
||||
lda pound ; set {!} as return line #
|
||||
sta bang
|
||||
lda lparen+1
|
||||
lda pound+1
|
||||
sta bang+1
|
||||
inc bang ; + 1
|
||||
bne goto11
|
||||
|
|
@ -853,11 +872,11 @@ goto11:
|
|||
ldy arg+3 ; is physical address pointer ?
|
||||
cpy #$ff
|
||||
beq goto3
|
||||
ora lparen ; direct mode ?
|
||||
ora pound ; direct mode ?
|
||||
beq goto12
|
||||
cpy lparen+1 ; set carry flag for find
|
||||
cpy pound+1 ; set carry flag for find
|
||||
bne goto2
|
||||
cpx lparen
|
||||
cpx pound
|
||||
bne goto2
|
||||
ldy #4 ; same line - start over
|
||||
jmp exec
|
||||
|
|
@ -878,12 +897,7 @@ jstart3:
|
|||
goto12:
|
||||
clc ; from start of prog
|
||||
goto2:
|
||||
; tya ; different line
|
||||
; pha ; invalidate {;}
|
||||
; txa ; restore line # low
|
||||
; jmp exec3 ; store new line in {#}
|
||||
|
||||
stx pound ; store target
|
||||
stx pound ; line # goto - store target
|
||||
sty pound+1
|
||||
jsr find
|
||||
bcs jstart3 ; end of program
|
||||
|
|
@ -910,11 +924,9 @@ goto4:
|
|||
goto7:
|
||||
ldy #1 ; load line #
|
||||
lda (at),y
|
||||
sta lparen
|
||||
sta pound
|
||||
iny
|
||||
lda (at),y
|
||||
sta lparen+1
|
||||
sta pound+1
|
||||
ldy #4
|
||||
jmp exec
|
||||
|
|
@ -970,57 +982,20 @@ prnum3:
|
|||
; array element expression enclosed in {: )}, or a
|
||||
; system variable (which may have side-effects)
|
||||
; entry: @[y] -> expression text, x -> argument
|
||||
; uses: getval:, oper:, {@}, argument stack area
|
||||
; uses: getval:, {@}, argument stack area
|
||||
; exit: arg[x] = result, @[y] -> next text
|
||||
;
|
||||
eval:
|
||||
; lda #0
|
||||
; sta 0,x ; start evaluation by simulating
|
||||
; sta 1,x ; {0+expression}
|
||||
; lda #'+'
|
||||
jsr getval ; arg[x] = value of first term
|
||||
jmp eval_gb ; startup skipping simulation
|
||||
notdn:
|
||||
pha ; stack alleged operator
|
||||
inx ; advance the argument stack
|
||||
inx ; pointer
|
||||
jsr getval ; arg[x+2] = value of next term
|
||||
dex
|
||||
dex
|
||||
pla ; retrieve and apply the operator
|
||||
jsr oper ; to arg[x], arg[x+2]
|
||||
; jsr getbyte ; end of expression?
|
||||
; beq evalrts ; (null or right parenthesis)
|
||||
; iny
|
||||
eval_gb: ; inline getbyte
|
||||
lda (at),y
|
||||
beq evalrts
|
||||
cmp #';' ; statement delimiter ?
|
||||
beq evalrts
|
||||
iny ; skip over any space char(s)
|
||||
cmp #' ' ; is space?
|
||||
beq eval_gb ; end inline
|
||||
|
||||
cmp #')' ; no: skip over the operator
|
||||
bne notdn ; and continue the evaluation
|
||||
evalrts:
|
||||
rts ; yes: return with final result
|
||||
;-----------------------------------------------------;
|
||||
; Get numeric value of the term at @[y] into var[x]
|
||||
; Some examples of valid terms: 123, $, H, (15-:J)/?)
|
||||
;
|
||||
getval:
|
||||
; jsr cvbin ; decimal number at @[y]?
|
||||
; lda #0
|
||||
; sta 0,x ; var[x] = 0
|
||||
; sta 1,x
|
||||
lda (at),y ; get variable or constant
|
||||
bpl getvar
|
||||
; cmp ';'
|
||||
; beq getrts
|
||||
iny
|
||||
; cmp #' ' ; skip space
|
||||
; beq getval
|
||||
; get constant
|
||||
cmp #$fd ; constant type ?
|
||||
bcs getword
|
||||
|
|
@ -1075,10 +1050,6 @@ getv_byp:
|
|||
cmp #$60 ; line # variable
|
||||
bcs gotomark
|
||||
|
||||
; first set var[x] to the named variable's address,
|
||||
; then replace that address with the variable's actual
|
||||
; value before returning
|
||||
|
||||
sty dolr ; get simple variable
|
||||
asl a
|
||||
ora #$80
|
||||
|
|
@ -1160,7 +1131,7 @@ in_val3:
|
|||
; Set var[x] to the address of the variable named in a
|
||||
; entry: a holds variable name, @[y] -> text holding
|
||||
; array index expression (if a = ':')
|
||||
; uses: plus, eval, oper8d, {@ &}
|
||||
; uses: eval, {@ &}
|
||||
; exit: (eq): var[x] -> variable, @[y] unchanged
|
||||
; (ne): var[x] -> array element,
|
||||
; @[y] -> following text
|
||||
|
|
@ -1172,11 +1143,14 @@ convp_array:
|
|||
jsr eval ; yes: evaluate array index at
|
||||
asl 0,x ; @[y] and advance y
|
||||
rol 1,x
|
||||
clc
|
||||
lda ampr ; var[x] -> array element
|
||||
sta 2,x ; at address 2*index+&
|
||||
adc 0,x ; at address 2*index+&
|
||||
sta 0,x
|
||||
lda ampr+1
|
||||
sta 3,x
|
||||
bne plus ; (always taken)
|
||||
adc 1,x
|
||||
sta 1,x
|
||||
rts
|
||||
; The following section is designed to translate the
|
||||
; named simple variable from its ASCII value to its
|
||||
; zero-page address. In this case, 'A' translates
|
||||
|
|
@ -1197,7 +1171,7 @@ simple:
|
|||
; exit: overflow is ignored/discarded, var[x+2] and
|
||||
; {>} are modified, a = 0
|
||||
;
|
||||
mul:
|
||||
op_mul:
|
||||
lda 0,x
|
||||
sta gthan
|
||||
lda 1,x ; {>} = var[x]
|
||||
|
|
@ -1212,7 +1186,6 @@ mul2:
|
|||
lsr gthan+1
|
||||
ror gthan ; {>} /= 2
|
||||
bcc mul3
|
||||
; jsr plus ; form the product in var[x]
|
||||
clc ; inline plus
|
||||
lda 0,x
|
||||
adc 2,x
|
||||
|
|
@ -1227,44 +1200,51 @@ mul3:
|
|||
ora 3,x ; loop until var[x+2] = 0
|
||||
bne mul2
|
||||
mulrts:
|
||||
rts
|
||||
jmp eval_gb
|
||||
;-----------------------------------------------------;
|
||||
; var[x] += var[x+2]
|
||||
; 14 bytes
|
||||
plus:
|
||||
;
|
||||
op_plus:
|
||||
clc
|
||||
lda 0,x
|
||||
adc 2,x
|
||||
sta 0,x
|
||||
lda 1,x
|
||||
adc 3,x
|
||||
sta 1,x
|
||||
rts
|
||||
jmp op_ret
|
||||
;-----------------------------------------------------;
|
||||
; expects: -
|
||||
;
|
||||
then_:
|
||||
lda 0,x
|
||||
ora 1,x
|
||||
beq then_exit
|
||||
else_true:
|
||||
lda 2,x
|
||||
sta 0,x
|
||||
lda 3,x
|
||||
sta 1,x
|
||||
then_exit:
|
||||
rts
|
||||
;-----------------------------------------------------;
|
||||
; expects: -
|
||||
;
|
||||
else_:
|
||||
op_else:
|
||||
lda 0,x
|
||||
ora 1,x
|
||||
beq else_true
|
||||
lda #0
|
||||
sta 0,x
|
||||
sta 1,x
|
||||
rts
|
||||
jmp op_ret
|
||||
;-----------------------------------------------------;
|
||||
; var[x] -= var[x+2]
|
||||
; expects: (cs)
|
||||
;
|
||||
op_minus:
|
||||
lda 0,x
|
||||
sbc 2,x
|
||||
sta 0,x
|
||||
lda 1,x
|
||||
sbc 3,x
|
||||
jmp op_ret
|
||||
;-----------------------------------------------------;
|
||||
; expects: -
|
||||
;
|
||||
op_then:
|
||||
lda 0,x
|
||||
ora 1,x
|
||||
beq eval_gb
|
||||
else_true:
|
||||
lda 2,x
|
||||
sta 0,x
|
||||
lda 3,x
|
||||
jmp op_ret
|
||||
;-----------------------------------------------------;
|
||||
; Apply the binary operator in a to var[x] and var[x+2]
|
||||
; Valid VTL02C operators are {* + / [ ] - | ^ & < = >}
|
||||
|
|
@ -1272,25 +1252,51 @@ else_:
|
|||
; An undefined operator will be interpreted as one of
|
||||
; the three comparison operators
|
||||
;
|
||||
notdn:
|
||||
pha ; stack alleged operator
|
||||
inx ; advance the argument stack
|
||||
inx ; pointer
|
||||
jsr getval ; arg[x+2] = value of next term
|
||||
dex
|
||||
dex
|
||||
pla ; retrieve and apply the operator
|
||||
oper:
|
||||
cmp #'+' ; addition operator?
|
||||
beq plus
|
||||
cmp #'*' ; multiplication operator?
|
||||
beq mul
|
||||
cmp #'/' ; division operator?
|
||||
beq div
|
||||
cmp #'[' ; "then" operator?
|
||||
beq then_
|
||||
cmp #']' ; "else" operator?
|
||||
beq else_
|
||||
bcs op_byp1
|
||||
cmp #'+' ; addition operator?
|
||||
beq op_plus
|
||||
cmp #'*' ; multiplication operator?
|
||||
beq op_mul
|
||||
cmp #'-' ; subtraction operator?
|
||||
beq minus
|
||||
cmp #OP_OR ; bit-wise or operator?
|
||||
beq or_
|
||||
cmp #'^' ; bit-wise xor operator?
|
||||
beq xor_
|
||||
beq op_minus
|
||||
cmp #'&' ; bit-wise and operator?
|
||||
beq and_
|
||||
beq op_and
|
||||
if OP_OR < '/'
|
||||
cmp #OP_OR ; bit-wise or operator?
|
||||
beq op_or
|
||||
endif
|
||||
op_byp1:
|
||||
beq op_div
|
||||
cmp #'[' ; "then" operator?
|
||||
bcc op_byp2
|
||||
beq op_then
|
||||
cmp #']' ; "else" operator?
|
||||
beq op_else
|
||||
if OP_OR > '/'
|
||||
cmp #OP_OR ; bit-wise or operator?
|
||||
beq op_or
|
||||
endif
|
||||
cmp #'^' ; bit-wise xor operator?
|
||||
beq op_xor
|
||||
cmp #'}' ; shift right operator?
|
||||
bne skp_shr
|
||||
jmp op_shr
|
||||
skp_shr:
|
||||
cmp #'{' ; shift left operator
|
||||
bne skp_shl
|
||||
jmp op_shl
|
||||
skp_shl:
|
||||
op_byp2:
|
||||
; - - - - - - - - - - - - - - - - - - - - - - - - - - ;
|
||||
; Apply comparison operator in a to var[x] and var[x+2]
|
||||
; and place result in var[x] (1: true, 0: false)
|
||||
|
|
@ -1298,7 +1304,6 @@ oper:
|
|||
;
|
||||
eor #'<' ; 0: '<' 1: '=' 2: '>'
|
||||
sta gthan ; other values in a are undefined,
|
||||
; jsr minus ; but _will_ produce some result
|
||||
lda 0,x ; inline minus
|
||||
sbc 2,x
|
||||
sta 0,x
|
||||
|
|
@ -1318,62 +1323,60 @@ oper8c:
|
|||
and #1 ; var[x] = 1 (true), 0 (false)
|
||||
sta 0,x
|
||||
lda #0
|
||||
sta 1,x
|
||||
rts
|
||||
;-----------------------------------------------------;
|
||||
; var[x] -= var[x+2]
|
||||
; expects: (cs)
|
||||
; 13 bytes
|
||||
minus:
|
||||
lda 0,x
|
||||
sbc 2,x
|
||||
sta 0,x
|
||||
lda 1,x
|
||||
sbc 3,x
|
||||
sta 1,x
|
||||
rts
|
||||
op_ret
|
||||
sta 1,x ; store result high
|
||||
eval_gb:
|
||||
lda (at),y ; get next operator
|
||||
beq evalrts
|
||||
cmp #';' ; statement delimiter ?
|
||||
beq evalrts
|
||||
iny ; skip over any space char(s)
|
||||
cmp #' ' ; is space?
|
||||
beq eval_gb ; end inline
|
||||
|
||||
cmp #')' ; no: skip over the operator
|
||||
bne notdn ; and continue the evaluation
|
||||
evalrts:
|
||||
rts ; yes: return with final result
|
||||
;-----------------------------------------------------;
|
||||
; var[x] &= var[x+2]
|
||||
; expects: -
|
||||
; 13 bytes
|
||||
and_:
|
||||
;
|
||||
op_and:
|
||||
lda 0,x
|
||||
and 2,x
|
||||
sta 0,x
|
||||
lda 1,x
|
||||
and 3,x
|
||||
sta 1,x
|
||||
rts
|
||||
jmp op_ret
|
||||
;-----------------------------------------------------;
|
||||
; var[x] |= var[x+2]
|
||||
; expects: -
|
||||
; 13 bytes
|
||||
or_:
|
||||
;
|
||||
op_or:
|
||||
lda 0,x
|
||||
ora 2,x
|
||||
sta 0,x
|
||||
lda 1,x
|
||||
ora 3,x
|
||||
sta 1,x
|
||||
rts
|
||||
jmp op_ret
|
||||
;-----------------------------------------------------;
|
||||
; var[x] ^= var[x+2]
|
||||
; expects: -
|
||||
; 13 bytes
|
||||
xor_:
|
||||
;
|
||||
op_xor:
|
||||
lda 0,x
|
||||
eor 2,x
|
||||
sta 0,x
|
||||
lda 1,x
|
||||
eor 3,x
|
||||
sta 1,x
|
||||
rts
|
||||
jmp op_ret
|
||||
;-----------------------------------------------------;
|
||||
; 16-bit unsigned division routine
|
||||
; var[x] /= var[x+2], {%} = remainder, {>} modified
|
||||
; var[x] /= 0 produces {%} = var[x], var[x] = 65535
|
||||
; 43 bytes
|
||||
div:
|
||||
;
|
||||
op_div:
|
||||
lda #0
|
||||
sta remn ; {%} = 0
|
||||
sta remn+1
|
||||
|
|
@ -1397,7 +1400,26 @@ div1:
|
|||
div2:
|
||||
dec gthan
|
||||
bne div1 ; loop 16 times
|
||||
rts
|
||||
sop_ret
|
||||
jmp eval_gb
|
||||
;-----------------------------------------------------;
|
||||
; var[x] shifted right by var[x+2] places
|
||||
;
|
||||
op_shr:
|
||||
dec 2,x
|
||||
bmi sop_ret
|
||||
lsr 1,x
|
||||
ror 0,x
|
||||
jmp op_shr
|
||||
;-----------------------------------------------------;
|
||||
; var[x] shifted left by var[x+2] places
|
||||
;
|
||||
op_shl:
|
||||
dec 2,x
|
||||
bmi sop_ret
|
||||
asl 0,x
|
||||
rol 1,x
|
||||
jmp op_shl
|
||||
;-----------------------------------------------------;
|
||||
; If text at @[y] is a decimal constant, translate it
|
||||
; into var[x] (discarding any overflow) and update y
|
||||
|
|
@ -1405,8 +1427,8 @@ div2:
|
|||
; leading space characters are skipped, but
|
||||
; any spaces encountered after a conversion
|
||||
; has begun will end the conversion.
|
||||
; used by: user:, getval:
|
||||
; uses: mul:, plus:, var[x], var[x+2], {@ > ?}
|
||||
; used by: user:, d2b:
|
||||
; uses: var[x], var[x+2], {@ > ?}
|
||||
; exit: (ne): var[x] = constant, @[y] -> next text
|
||||
; (eq): var[x] = 0, @[y] unchanged
|
||||
; (cs): in all but the truly strangest cases
|
||||
|
|
@ -1415,9 +1437,6 @@ cvbin:
|
|||
lda #0
|
||||
sta 0,x ; var[x] = 0
|
||||
sta 1,x
|
||||
; sta 3,x
|
||||
; jsr getbyte ; skip any leading spaces
|
||||
; sty ques ; save pointer
|
||||
cvb_gb1: ; inline getbyte
|
||||
sty ques ; save pointer
|
||||
lda (at),y
|
||||
|
|
@ -1435,10 +1454,6 @@ cvbin2:
|
|||
cmp #10 ; decimal digit then stop
|
||||
bcs cvbin3 ; the conversion
|
||||
pha ; save decimal digit
|
||||
; lda #10
|
||||
; sta 2,x
|
||||
; jsr mul ; var[x] *= 10
|
||||
; sta 3,x
|
||||
lda 1,x ; inline multiply by 10
|
||||
sta gthan+1
|
||||
lda 0,x
|
||||
|
|
@ -1456,8 +1471,6 @@ cvbin2:
|
|||
rol a
|
||||
sta 1,x ; end inline
|
||||
pla ; retrieve decimal digit
|
||||
; sta 2,x
|
||||
; jsr plus ; var[x] += digit
|
||||
clc ; inline add digit
|
||||
adc 0,x
|
||||
sta 0,x
|
||||
|
|
@ -1479,8 +1492,6 @@ cvbin3:
|
|||
; uses: inch:, outnl:, linbuf, {@}
|
||||
; exit: @[y] -> linbuf
|
||||
;
|
||||
;newln:
|
||||
; jsr outnl ; yes: discard entire line
|
||||
inln:
|
||||
ldy #lo(linbuf); entry point: start a fresh line
|
||||
sty at ; {@} -> input line buffer
|
||||
|
|
@ -1533,7 +1544,7 @@ inlnesc1:
|
|||
; exit: (cs): {@}, x:a and {(} undefined, y = 3
|
||||
; (cc): {@} -> beginning of found line, y = 3,
|
||||
; x:a = {(} = actual found line number
|
||||
; 62 bytes
|
||||
;
|
||||
find:
|
||||
ldx #hi(prgm)
|
||||
lda #lo(prgm)
|
||||
|
|
@ -1674,18 +1685,6 @@ d2bex:
|
|||
rts
|
||||
jd2blp:
|
||||
jmp d2blp
|
||||
;-----------------------------------------------------;
|
||||
; Fetch a byte at @[y], ignoring space characters
|
||||
; 10 bytes
|
||||
;skpbyte:
|
||||
; iny ; skip over current char
|
||||
;getbyte:
|
||||
; lda (at),y
|
||||
; beq getbyt2
|
||||
; cmp #' '
|
||||
; beq skpbyte ; skip over any space char(s)
|
||||
;getbyt2:
|
||||
; rts
|
||||
;============ Original I/O subroutines ===============;
|
||||
;-----------------------------------------------------;
|
||||
; Check for user keypress and return with (cc) if none
|
||||
|
|
@ -1730,15 +1729,11 @@ timr_adr = timr_var*2|$80
|
|||
inkey:
|
||||
lda acia_rx ; Is there a character waiting?
|
||||
beq inkeyr ; no: return
|
||||
; cmp #3 ; is ctrl-c
|
||||
; beq istart ; yes: abort to OK prompt
|
||||
jsr test_abort
|
||||
inkeyp:
|
||||
lda acia_rx ; pause until next key
|
||||
beq inkeyp
|
||||
jsr test_abort
|
||||
; cmp #3 ; is ctrl-c
|
||||
; beq istart ; yes: abort to OK prompt
|
||||
inkeyr:
|
||||
rts
|
||||
; - - - - - - - - - - - - - - - - - - - - - - - - - - ;
|
||||
|
|
@ -1769,13 +1764,10 @@ skip_esc_discard:
|
|||
cpy #1
|
||||
bne inch ; discard escape sequence
|
||||
lda #27 ; escape only - send to vtl
|
||||
; ldy dolr
|
||||
; rts
|
||||
skip_esc_no
|
||||
ldy dolr ; restore y reg
|
||||
inch2:
|
||||
and #$7f ; ensure char is positive ascii
|
||||
; cmp #$03 ; ctrl-C?
|
||||
jsr test_abort
|
||||
cmp #BS ; only echo printable, bs & cr
|
||||
beq outch
|
||||
|
|
|
|||
Loading…
Reference in New Issue