LCDPRINT by using formular evaluator

README.md

@@ -7,8 +7,9 @@ But if you're following along with earlier videos, the "code" link below will ta
 |                                | Video                                                    | Code               |
 |--------------------------------|----------------------------------------------------------|--------------------|
 | ![Video thumbnail][thumbnail1] | [Running MSBASIC on my breadboard 6502 computer][video1] | [a15c8e0][commit1] |
-| ![Video thumbnail][thumbnail2] | [How input buffering works][video2]                      | [54ef9ac][commit2]  |
-| ![Video thumbnail][thumbnail3] | [RS232 flow control][video3]                      | [master][commit3]  |
+| ![Video thumbnail][thumbnail2] | [How input buffering works][video2]                      | [54ef9ac][commit2] |
+| ![Video thumbnail][thumbnail2] | [RS232 flow control][video3]                             | [c21542e][commit3] |
+| ![Video thumbnail][thumbnail4] | [Hacking Microsoft BASIC][video4]                        | [master][commit4]  |
 
 [thumbnail1]: https://i.ytimg.com/vi/XlbPnihCM0E/mqdefault.jpg
 [video1]: https://youtu.be/XlbPnihCM0E
@@ -22,7 +23,11 @@ But if you're following along with earlier videos, the "code" link below will ta
 
 [thumbnail3]: https://i.ytimg.com/vi/LuKMVXWD7FY/mqdefault.jpg
 [video3]: https://youtu.be/LuKMVXWD7FY
-[commit3]: https://github.com/beneater/msbasic/tree/master
+[commit3]: https://github.com/beneater/msbasic/tree/c21542e724b3da45ba3790405c2cf85e77bc1ad4
+
+[thumbnail4]: https://i.ytimg.com/vi/gOwi2p1pzVM/mqdefault.jpg
+[video4]: https://youtu.be/gOwi2p1pzVM
+[commit4]: https://github.com/beneater/msbasic/tree/master
 
 Below is the original README:
 

init.s

@@ -123,6 +123,9 @@ COLD_START:
         lda     #WIDTH2
         sta     Z18
   .endif
+  .ifdef EATER
+        jsr     LCDINIT
+  .endif
 .endif
 
 ; All non-CONFIG_SMALL versions of BASIC have

lcd.s

@@ -0,0 +1,149 @@
+.segment "CODE"
+.ifdef EATER
+PORTB = $6000
+DDRB = $6002
+E  = %01000000
+RW = %00100000
+RS = %00010000
+
+lcd_wait:
+  pha
+  lda #%11110000  ; LCD data is input
+  sta DDRB
+lcdbusy:
+  lda #RW
+  sta PORTB
+  lda #(RW | E)
+  sta PORTB
+  lda PORTB       ; Read high nibble
+  pha             ; and put on stack since it has the busy flag
+  lda #RW
+  sta PORTB
+  lda #(RW | E)
+  sta PORTB
+  lda PORTB       ; Read low nibble
+  pla             ; Get high nibble off stack
+  and #%00001000
+  bne lcdbusy
+
+  lda #RW
+  sta PORTB
+  lda #%11111111  ; LCD data is output
+  sta DDRB
+  pla
+  rts
+
+LCDINIT:
+  lda #$ff ; Set all pins on port B to output
+  sta DDRB
+
+  lda #%00000011 ; Set 8-bit mode
+  sta PORTB
+  ora #E
+  sta PORTB
+  and #%00001111
+  sta PORTB
+
+  lda #%00000011 ; Set 8-bit mode
+  sta PORTB
+  ora #E
+  sta PORTB
+  and #%00001111
+  sta PORTB
+
+  lda #%00000011 ; Set 8-bit mode
+  sta PORTB
+  ora #E
+  sta PORTB
+  and #%00001111
+  sta PORTB
+
+  ; Okay, now we're really in 8-bit mode.
+  ; Command to get to 4-bit mode ought to work now
+  lda #%00000010 ; Set 4-bit mode
+  sta PORTB
+  ora #E
+  sta PORTB
+  and #%00001111
+  sta PORTB
+
+  lda #%00101000 ; Set 4-bit mode; 2-line display; 5x8 font
+  jsr lcd_instruction
+  lda #%00001110 ; Display on; cursor on; blink off
+  jsr lcd_instruction
+  lda #%00000110 ; Increment and shift cursor; don't shift display
+  jsr lcd_instruction
+  lda #%00000001 ; Clear display
+  jsr lcd_instruction
+  rts
+
+
+LCDCMD:
+  jsr GETBYT
+  txa
+lcd_instruction:
+  jsr lcd_wait
+  pha
+  lsr
+  lsr
+  lsr
+  lsr            ; Send high 4 bits
+  sta PORTB
+  ora #E         ; Set E bit to send instruction
+  sta PORTB
+  eor #E         ; Clear E bit
+  sta PORTB
+  pla
+  and #%00001111 ; Send low 4 bits
+  sta PORTB
+  ora #E         ; Set E bit to send instruction
+  sta PORTB
+  eor #E         ; Clear E bit
+  sta PORTB
+  rts
+
+LCDPRINT:
+  jsr FRMEVL            ; Evaluate formular
+  bit VALTYP            ; Is it a string?
+  bmi lcd_print_string  ; Yes
+  jsr FOUT              ; Format floating point output
+  jsr STRLIT            ; Build string descriptor
+lcd_print_string:
+  jsr FREFAC            ; Returns temp pointer to string
+  tax                   ; Put count to counter
+  ldy #0
+  inx                   ; Move one ahead
+lcd_print_next:
+  dex
+  beq lcd_print_end     ; All done
+  lda (INDEX),y         ; Load char of string
+  jsr lcd_print_char    ; Output to lcd
+  iny
+  bne lcd_print_next    ; Go on with next char
+lcd_print_end:
+  rts
+
+lcd_print_char:
+  jsr lcd_wait
+  pha
+  lsr
+  lsr
+  lsr
+  lsr             ; Send high 4 bits
+  ora #RS         ; Set RS
+  sta PORTB
+  ora #E          ; Set E bit to send instruction
+  sta PORTB
+  eor #E          ; Clear E bit
+  sta PORTB
+  pla
+  and #%00001111  ; Send low 4 bits
+  ora #RS         ; Set RS
+  sta PORTB
+  ora #E          ; Set E bit to send instruction
+  sta PORTB
+  eor #E          ; Clear E bit
+  sta PORTB
+  rts
+
+.endif

make.cmd

@@ -0,0 +1,10 @@
+@echo off
+if not exist tmp (
+    mkdir tmp
+)
+
+for %%i in (cbmbasic1 cbmbasic2 kbdbasic osi kb9 applesoft microtan aim65 sym1 eater) do (
+    echo %%i
+    C:\CC65\bin\ca65 -D %%i msbasic.s -o tmp\%%i.o
+    C:\CC65\bin\ld65 -C %%i.cfg tmp\%%i.o -o tmp\%%i.bin -Ln tmp\%%i.lbl
+)

msbasic.s

@@ -33,3 +33,4 @@
 .include "trig.s"
 .include "init.s"
 .include "extra.s"
+.include "lcd.s"

token.s

@@ -78,6 +78,10 @@
 		keyword_rts "PRT", PRT
 .endif
 		keyword_rts "NEW", NEW
+.ifdef EATER
+		keyword_rts "LCDCMD", LCDCMD
+		keyword_rts "LCDPRINT", LCDPRINT
+.endif
 
 		count_tokens