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view src/print.s @ 75:5f8f0b0781e8
Split some code into separate files for easier management (3)
Because the source for lwbasic is so large, split it into several
different files to make it easier to navigate and modify. This is
part three of the split. Includes a file missing from part one.
| author | William Astle <lost@l-w.ca> |
|---|---|
| date | Sun, 06 Aug 2023 00:41:26 -0600 |
| parents | |
| children | bb50ac9fdf37 |
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*pragmapush list *pragma list ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ; Print out an unsigned 16 bit value in D to the selected output stream print_uint16d pshs d,x,y,u ; save number and make some temporaries on the stack leay 2,s ; point to start of buffer ldu #10000 ; do the 10000s digit bsr print_uint16d4 ldu #1000 ; do the 1000s digit bsr print_uint16d4 ldu #100 ; do the 100s digit bsr print_uint16d4 ldu #10 ; do the 10s digit bsr print_uint16d4 puls d ; get back number residue and clean up stack addb #0x30 ; convert 1s digit to number stb ,y ; stash it clr 1,y ; NUL terminate it leay ,s ; point to start of converted number print_uint16d0 lda ,y ; get digit at start cmpa #0x30 ; zero digit? bne print_uint16d1 ; brif not - we can just show the number from here ldb 1,y ; end of number? beq print_uint16d1 ; brif so - show the zero anyway leay 1,y ; move past the zero bra print_uint16d0 ; see if we have more zeroes to skip print_uint16d1 lda ,y+ ; get number digit beq print_uint16d2 ; brif end of number jsr writechr ; output the digit bra print_uint16d1 ; handle next digit print_uint16d2 leas 6,s ; clean up the stack rts print_uint16d4 lda #0x30-1 ; init digit value pshs a,u ; save the digit position and digit value ldd 5,s ; get back residue print_uint16d5 inc ,s ; bump digit subd 1,s ; subtract out place value bcc print_uint16d5 ; brif we haven't got the right digit yet addd 1,s ; restore residue std 5,s ; save new residue puls a,u ; get back digit and place value off stack sta ,y+ ; save digit in buffer rts ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ; PRINT command cmd_print beq cmd_printeol ; brif no argument - do a newline cmd_print0 cmpa #'; ; semicolon? bne cmd_print1 ; brif not jsr nextchar ; skip the semicolon bne cmd_print0 ; brif not end of the statement rts cmd_print1 jsr eval_expr ; evaluate the expression ldb val0+val.type ; get value type cmpb #valtype_int ; integer? beq cmd_printint ; brif so - print integer lda #'! ; flag unknown expression type jsr console_outchr jsr console_outchr jsr console_outchr cmd_printnext jsr curchar ; see what we have here bra cmd_print ; and go process cmd_printeol jmp console_outnl ; do a newline and return cmd_printint leas -12,s ; make a buffer leay ,s ; point to buffer lda #0x20 ; default sign (positive) ldb val0+val.int ; is it negative? bpl cmd_printint0 ; brif not jsr val_negint32 ; negate the integer lda #'- ; negative sign cmd_printint0 sta ,y+ ; save sign ldu #cmd_printintpc ; point to positive constant table ldx #10 ; there are 10 constants to process ; subtraction loop - positive residue cmd_printint1 lda #'0-1 ; initialize digit sta ,y cmd_printint2 inc ,y ; bump digit ldd val0+val.int+2 ; subtract constant subd 2,u std val0+val.int+2 ldd val0+val.int sbcb 1,u sbca ,u std val0+val.int bcc cmd_printint2 ; brif we didn't go negative ldd val0+val.int+2 ; undo last subtract addd 2,u std val0+val.int+2 ldd val0+val.int adcb 1,u adca ,u std val0+val.int leay 1,y ; move to next digit in buffer leau 4,u ; move to next constant leax -1,x ; done all constants? bne cmd_printint1 ; brif not - done all cmd_printint5 clr ,y ; NUL terminate the string leax 1,s ; point past the sign cmd_printint6 lda ,x+ ; get digit beq cmd_printint8 ; brif end of number cmpa #'0 ; is it a zero? beq cmd_printint6 ; brif so - skip it cmd_printint7 lda ,s ; get the sign sta ,--x ; put it at the start of the number jsr console_outstr ; display the number leas 12,s ; clean up stack bra cmd_printnext ; go print the next thing cmd_printint8 leax -1,x ; restore one of the zeros bra cmd_printint7 ; go finish up cmd_printintpc fqb 1000000000 ; 10^9 fqb 100000000 ; 10^8 fqb 10000000 ; 10^7 fqb 1000000 ; 10^6 fqb 100000 ; 10^5 fqb 10000 ; 10^4 fqb 1000 ; 10^3 fqb 100 ; 10^2 fqb 10 ; 10^1 fqb 1 ; 10^0 *pragmapop list