diff options
Diffstat (limited to 'programs')
| -rw-r--r-- | programs/forg.s | 17 | ||||
| -rw-r--r-- | programs/hex-to-bcd.s | 7 | ||||
| -rw-r--r-- | programs/subasm.s | 296 |
3 files changed, 269 insertions, 51 deletions
diff --git a/programs/forg.s b/programs/forg.s new file mode 100644 index 0000000..3e6aea1 --- /dev/null +++ b/programs/forg.s @@ -0,0 +1,17 @@ +forg: + iny ; Increment offset. + lda buf, y + jsr iswhite + bcs forg ; Reset y, if we hit the null terminator. + cmp #$2E ; Is this character a '.'? + bne forg_exit ; No, so return. + sty org ; Yes, so store the origin. +forg_end: + iny ; Increment offset. + lda buf, y + jsr istoken + bcs forg_end + dey + sty scr_col +forg_exit: + rts ; End of forg. diff --git a/programs/hex-to-bcd.s b/programs/hex-to-bcd.s new file mode 100644 index 0000000..53a3ff2 --- /dev/null +++ b/programs/hex-to-bcd.s @@ -0,0 +1,7 @@ +hex_to_bcd: + pla #1 ; Get argument. + div #10 ; Divide A by 10. + lsl #4 ; Shift the result left by 4 bits. + oab ; Or the result, with the remainder. + pha #1 ; Push the packed BCD result to the stack. + rts ; Return the result. diff --git a/programs/subasm.s b/programs/subasm.s index ddb7ba2..50f2e8d 100644 --- a/programs/subasm.s +++ b/programs/subasm.s @@ -12,6 +12,111 @@ ver_txt: ver_num: .byte "0.1" +; Directives. +dir: + .byte "org" + .byte "byte" + .byte "word" + .byte "dword" + .byte "qword" + +; Instruction mnemonics. +mne: + .byte "CPS" + .byte "ADC" + .byte "AAB" + .byte "PHB" + .byte "PHP" + .byte "PHA" + .byte "PHY" + .byte "TAY" + .byte "PHX" + .byte "TAX" + .byte "TYX" + .byte "JMP" + .byte "SBC" + .byte "SAB" + .byte "PLB" + .byte "PLP" + .byte "PLA" + .byte "PLY" + .byte "TYA" + .byte "PLX" + .byte "TXA" + .byte "TXY" + .byte "JSR" + .byte "AND" + .byte "ABA" + .byte "STT" + .byte "TAB" + .byte "TSX" + .byte "BPO" + .byte "ORA" + .byte "OAB" + .byte "TBA" + .byte "SEI" + .byte "TXS" + .byte "BNG" + .byte "XOR" + .byte "XAB" + .byte "CLI" + .byte "BCS" + .byte "LSL" + .byte "LLB" + .byte "STB" + .byte "SEC" + .byte "STA" + .byte "STY" + .byte "STX" + .byte "BCC" + .byte "LSR" + .byte "LRB" + .byte "LDB" + .byte "CLC" + .byte "LDA" + .byte "LDY" + .byte "LDX" + .byte "BEQ" + .byte "ROL" + .byte "RLB" + .byte "SSP" + .byte "BNE" + .byte "ROR" + .byte "RRB" + .byte "CSP" + .byte "BVS" + .byte "MUL" + .byte "MAB" + .byte "SEV" + .byte "BVC" + .byte "DIV" + .byte "DAB" + .byte "CLV" + .byte "RTS" + .byte "CMP" + .byte "CAB" + .byte "CPY" + .byte "CPX" + .byte "CPB" + .byte "ENT" + .byte "RTI" + .byte "INC" + .byte "IAB" + .byte "INY" + .byte "INX" + .byte "DEC" + .byte "DBA" + .byte "DEY" + .byte "DEX" + .byte "WAI" + .byte "JSL" + .byte "ASR" + .byte "ARB" + .byte "NOP" + .byte "RTL" + .byte "BRK" + + scr_row: .byte $0 scr_col: @@ -31,6 +136,13 @@ str_buf: .org $2000 buf: +.org $2400 +ptr1: + .qword $2500 + +ptr2: + .qword $2900 + ; Control Register. .org $C000 ctrl_reg: @@ -49,22 +161,22 @@ reset: cps ldx.w #$FFFF txs - ldy #$0 + ldy #0 jsr clr_buf - ldx.w #$0 ; Reset x. - ldy #$0 ; Reset y. + ldx.w #0 ; Reset x. + ldy #0 ; Reset y. jmp print_title read: lda ctrl_reg ; Is the keyboard ready? beq read ; Loop until the keyboard is ready. - lda #$0 ; Start resetting the control register. + lda #0 ; Start resetting the control register. sta ctrl_reg ; Reset the control register. jmp getchar ; We got a key. rset_x: - ldx #$0 ; Reset x. + ldx #0 ; Reset x. stx.w x rts @@ -94,7 +206,7 @@ getline: lda #$A sta scr ; Print newline inc scr_row - lda #$0 + lda #0 sta scr_col inc y jsr rset_x @@ -106,7 +218,7 @@ getchar: beq esc ; Yes, so start getting the escape code. cmp #$A ; Did the user type a newline? beq nl ; Yes, so start parsing the input. - cmp #$8 ; Did the user type a backspace? + cmp #8 ; Did the user type a backspace? beq bs ; Yes, so start checking the buffer. jsr echo ; Print character to screen. @@ -123,16 +235,16 @@ esc: sta c ; Store the escape code, until we need it. jsr isup ; Check if the user pressed up. lda d - cmp #$0 + cmp #0 bne esc_end jsr isdown ; Check if the user pressed down. lda d - cmp #$0 + cmp #0 bne esc_end - lda #$0 + lda #0 jsr isleft ; Check if the user pressed left. lda d - cmp #$0 + cmp #0 bne esc_end jsr isright ; Check if the user pressed right. esc_end: @@ -181,13 +293,13 @@ isleft_done: up: dec scr_row jsr update_pos - lda #$1 + lda #1 sta d jmp isup_done down: inc scr_row jsr update_pos - lda #$1 + lda #1 sta d jmp isdown_done right: @@ -197,7 +309,7 @@ right: left: dec scr_col jsr update_pos - lda #$1 + lda #1 sta d jmp isleft_done @@ -237,47 +349,81 @@ getcol: nl: sta scr ; Print newline. inc scr_row ; Move the cursor down one line. - lda #$0 ; Put a null terminator, in place of the newline. + lda #0 ; Put a null terminator, in place of the newline. sta scr_col ; Move the cursor back to column 0. - sta str_buf, y ; Place it into the input buffer. - ldy.w #$0 ; Reset y, to parse the input. + sta buf, y ; Place it into the input buffer. + ldy.w #0 ; Reset y, to parse the input. jsr parse ; Start parsing input. back: sta scr ; Print backspace. - lda #$0 ; Put a null terminator, in place of the backspace. - sta str_buf, y ; Place it into the input buffer. + lda #0 ; Put a null terminator, in place of the backspace. + sta buf, y ; Place it into the input buffer. dey ; Decrement buffer offset. dec scr_col jmp read ; Get next character. bs: - cpy #$0 ; Are we at the start of the buffer? + cpy #0 ; Are we at the start of the buffer? beq read ; We are, so do not store the backspace into the buffer. jmp back ; We are not, so add the backspace to the buffer. parse: - jmp parse ; Keep printing. - jsr clr_sbuf + jsr getdir + jsr rts -forg: +getdir: iny ; Increment offset. - lda str_buf, y + lda buf, y jsr iswhite - bcs forg ; Reset y, if we hit the null terminator. + bcs getdir ; Reset y, if we hit the null terminator. cmp #$2E ; Is this character a '.'? - bne forg_exit ; No, so return. - sty org ; Yes, so store the origin. -forg_end: + bne getdir_exit ; No, so return. + jsr clr_ptr + +getdir_end: iny ; Increment offset. - lda str_buf, y + lda buf, y + jsr iswhite + bcs getdir_cmp + ora #%00100000 ; Make character lower case. + sta (ptr1), y + jmp getdir_end +gettok: + ply #1 + iny +gettok2: + lda buf, y jsr istoken - bcs forg_end - dey - sty scr_col -forg_exit: - rts ; End of forg. + bcs gettok3 + jmp gettok2 +gettok3: + cmp #$ + cmp #$24 ; Is this character, a '$'? + beq getaddr ; Yes, so start getting the address. + + + +getdir_cmp: + phy #1 + ldy.w #0 + tyx +getdir_cpl: + ldb dir, x ; Start checking if the directive we're using, is "org". + stb (ptr2), y + beq getdir_scmp + inx + iny + jmp getdir_cpl +getdir_scmp: + ldy #0 + jsr strcmp + cpx #0 + beq getdir_tok +getdir_exit: + rts ; End of getdir. + istoken: cmp #$20 ; Is this character a space? @@ -288,7 +434,7 @@ istoken: beq istoken_f ; Yes, so return false. cmp #$3B ; Is this character a ';'? beq istoken_f ; Yes, so return false. - cmp #$0 ; Is this character a null terminator? + cmp #0 ; Is this character a null terminator? beq istoken_f ; Yes, so return false. sec ; Return true. rts ; End of istoken. @@ -299,7 +445,7 @@ istoken_f iswhite: cmp #$20 ; Is this character a space? beq iswhite_t ; Yes, so return true. - cmp #$09 ; Is this character a tab? + cmp #9 ; Is this character a tab? beq iswhite_t ; Yes, so return true. clc ; No, so return false. rts ; End of iswhite. @@ -308,7 +454,7 @@ iswhite_t: rts ; End of iswhite_t. rset_y: - ldy.w #$0 + ldy.w #0 jmp print_buf ; Print the input buffer. print_buf: @@ -325,15 +471,15 @@ spin: jmp spin clr_buf: - lda #$0 - cpy.w #$1000 + lda #0 + cpy.w #$3FF beq clr_end sta buf, y iny jmp clr_buf clr_sbuf: - lda #$0 - cpy.w #$40 + lda #0 + cpy.w #$1FF beq clr_end sta str_buf, y iny @@ -343,7 +489,7 @@ clr_end: rts echo: - sta a + tab ldx scr_col cpx #$4F bne echo_print @@ -351,17 +497,51 @@ echo: beq linewrap linewrap: inc scr_row - ldx #$0 + ldx #0 stx scr_col jsr update_pos echo_print: - lda a + tba sta scr ; Echo typed character. inc scr_col ; Increment the cursor's x coordinate. - sta str_buf, y ; Store typed character into the input buffer. + sta buf, y ; Store typed character into the input buffer. iny ; Increment the buffer offset. rts ; Return. +clr_ptr: + lda #0 + cpy.w #$3FF + beq ptr_end + sta (ptr1), y + sta (ptr2), y + iny + jmp clr_ptr +ptr_end: + rts + +strcmp: + lda (ptr1), y + cmp (ptr2), y + bne strcmp_l1 + tax + beq strcmp_l3 + iny + bne strcmp + jmp strcmp + + +strcmp_l1: + bcs strcmp_l2 + ldx #0 + dex + rts + +strcmp_l2: + ldx #1 +strcmp_l3: + rts + + .org $FFC0 .qword reset @@ -376,9 +556,23 @@ echo_print: .org $FFA0 .qword irq_routine -;.org $0 -;viewmem -;.org $100 -;viewmem -;q -done +.org $0 +v +.org $100 +v +.org $200 +v +.org $300 +v +.org $1000 +v +.org $1100 +v +.org $1200 +v +.org $1300 +v +.org $1400 +v +q + |