diff options
Diffstat (limited to 'ports.s')
| -rw-r--r-- | ports.s | 104 |
1 files changed, 53 insertions, 51 deletions
@@ -1,10 +1,12 @@ - ;; Routines to process OUT and IN instructions. This is the - ;; bit that's unique to TI calculators. +|| -*- gas -*- - ;; Port is in d0, byte is in d1 - ;; Destroys a0 + || Routines to process OUT and IN instructions. This is the + || bit that's unique to TI calculators. + + || Port is in d0, byte is in d1 + || Destroys a0 port_in: - andi.w #$ff,d0 + andi.w #0xff,d0 add.w d0,d0 add.w d0,d0 movea.l lut_ports_in(pc,d0),a0 @@ -270,8 +272,8 @@ lut_ports_in: .int port_in_ff port_out: - andi.w #$ff,d0 - ;; This is the fastest way to shift left 2 bits. :S + andi.w #0xff,d0 + || This is the fastest way to shift left 2 bits. :S add.w d0,d0 add.w d0,d0 movea.l lut_ports_out(pc,d0.w),a0 @@ -537,10 +539,10 @@ lut_ports_out: port_in_00: port_out_00: - ;; Temporary test harness. Writing to this port writes a - ;; character to the screen. + || Temporary test harness. Writing to this port writes a + || character to the screen. SAVEREG - andi.w #$ff,d1 + andi.w #0xff,d1 move.w d1,-(sp) jsr char_draw addq #2,sp @@ -555,7 +557,7 @@ port_in_03: port_out_03: port_in_04: port_out_04: - ;; Bank B paging, among other things + || Bank B paging, among other things SAVEREG move.b d1,-(a7) jsr bankswap_b_write @@ -567,7 +569,7 @@ port_in_05: port_out_05: port_in_06: port_out_06: - ;; Bank A paging + || Bank A paging SAVEREG move.b d1,-(a7) jsr bankswap_a_write @@ -604,7 +606,7 @@ port_in_10: .xref video_write .xref video_read - ;; LCD status + || LCD status clr.b d1 or.b video_increment,d1 or.b video_row,d1 @@ -614,7 +616,7 @@ port_in_10: rts port_out_10: - ;; LCD command + || LCD command tst.b d1 beq port_out_10_00 subq.b #1,d1 @@ -632,77 +634,77 @@ port_out_10: subq.b #1,d1 beq port_out_10_07 addq.b #7,d1 - cmpi.b #$0b,d1 ; power supply enhancement + cmpi.b #0x0b,d1 | power supply enhancement ble port_out_10_undef - cmpi.b #$13,d1 ; power supply level + cmpi.b #0x13,d1 | power supply level ble port_out_10_undef - cmpi.b #$17,d1 ; undefined + cmpi.b #0x17,d1 | undefined ble port_out_10_undef - cmpi.b #$18,d1 ; cancel test mode + cmpi.b #0x18,d1 | cancel test mode beq port_out_10_undef - cmpi.b #$1b,d1 ; undefined + cmpi.b #0x1b,d1 | undefined beq port_out_10_undef - cmpi.b #$1f,d1 ; enter test mode + cmpi.b #0x1f,d1 | enter test mode ble port_out_10_undef - cmpi.b #$3f,d1 ; set column + cmpi.b #0x3f,d1 | set column ble port_out_10_set_col - cmpi.b #$7f,d1 ; z-addressing - ble port_out_10_undef ; XXX? - cmpi.b #$df,d1 ; set row + cmpi.b #0x7f,d1 | z-addressing + ble port_out_10_undef | XXX? + cmpi.b #0xdf,d1 | set row ble port_out_10_set_row - ;; fallthrough: set contrast (unimplemented) + || fallthrough: set contrast (unimplemented) rts - ;; ... -port_out_10_00: ; 6-bit mode - move.b #$00,video_6bit + || ... +port_out_10_00: | 6-bit mode + move.b #0x00,video_6bit rts -port_out_10_01: ; 8-bit mode - move.b #$40,video_6bit +port_out_10_01: | 8-bit mode + move.b #0x40,video_6bit rts -port_out_10_02: ; screen off - move.b #$20,video_enabled +port_out_10_02: | screen off + move.b #0x20,video_enabled rts -port_out_10_03: ; screen on - move.b #$00,video_enabled +port_out_10_03: | screen on + move.b #0x00,video_enabled rts -port_out_10_04: ; x-- - move.b #$01,video_row - move.b #$00,video_increment +port_out_10_04: | x-- + move.b #0x01,video_row + move.b #0x00,video_increment rts -port_out_10_05: ; x++ - move.b #$01,video_row - move.b #$02,video_increment +port_out_10_05: | x++ + move.b #0x01,video_row + move.b #0x02,video_increment rts -port_out_10_06: ; y-- - move.b #$00,video_row - move.b #$00,video_increment +port_out_10_06: | y-- + move.b #0x00,video_row + move.b #0x00,video_increment rts -port_out_10_07: ; y++ - move.b #$00,video_row - move.b #$02,video_increment +port_out_10_07: | y++ + move.b #0x00,video_row + move.b #0x02,video_increment rts port_out_10_undef: rts port_out_10_set_col: - sub.b #$20,d1 + sub.b #0x20,d1 move.b d1,video_cur_col rts port_out_10_set_row: - sub.b #$80,d1 + sub.b #0x80,d1 move.b d1,video_cur_row rts port_in_11: - ;; LCD data + || LCD data SAVEREG jsr video_read - move.b d0,d1 ; return value + move.b d0,d1 | return value RESTREG rts port_out_11: - ;; LCD data + || LCD data SAVEREG move.b d1,-(a7) jsr video_write |