feat(hello_world): Split hello.oph into multiple files

4 files changed, 48 insertions, 47 deletions

diff --git a/hello_world/Makefile b/hello_world/Makefile
index 7bec999..016291a 100644
--- a/hello_world/Makefile
+++ b/hello_world/Makefile
@@ -4,7 +4,7 @@ VICEFLAGS=-VICIIfilter 0
 .PHONY: build execute run
 
 build:
-	ophis *.oph
+	ophis hello.oph
 
 execute:
 	$(VICE) $(VICEFLAGS) *.prg >/dev/null
diff --git a/hello_world/basic_starter.oph b/hello_world/basic_starter.oph
new file mode 100644
index 0000000..b893c08
--- /dev/null
+++ b/hello_world/basic_starter.oph
@@ -0,0 +1,28 @@
+; PRG format
+;   Contains two bytes of header data, address from which
+;   the rest of the file will be loaded into memory.
+; BASIC memory starts at addr 2048, we effectively place "10 SYS 2064"
+; and an end of program after it. Then immedately afterwards
+; we place our command on addr 2064.
+;   When BASIC loads up, it runs "10 SYS 2064" and passes up execution there.
+;   Then, when we return, we get a zero which indicates termination.
+
+; The starting address is defined by the value (label or alias) "main".
+; Since in basic we need to provide a decimal string, but we store a decimal value, we need
+; to do this complicated convertion.
+.alias main_addr_ch1 '0 + main / 10000                         ; 65535 -> 6
+.alias main_addr_ch2 '0 + [main - main / 10000 * 10000] / 1000 ; 65535 -> 65535 - 60000 = 5535 / 1000 = 5
+.alias main_addr_ch3 '0 + [main - main / 1000 * 1000] / 100    ; 65535 -> 65535 - 65000 = 535 / 100 = 5
+.alias main_addr_ch4 '0 + [main - main / 100 * 100] / 10       ; 65535 -> 65535 - 65500 = 35 / 10 = 3
+.alias main_addr_ch5 '0 + main - main / 10 * 10                ; 65535 -> 65535 - 65530 = 5
+
+.word $0801 ; Header -- addr 2049
+.org  $0801 ; Program Counter
+
+.scope
+         .word _eop             ; Next line addr  (I guess it is used to tell how long the line is?)
+         .word 10               ; 10              (line of BASIC program)
+         .byte $9e," "          ; SYS 2064        (opcode for SYS and null terminated string)
+         .byte main_addr_ch1,main_addr_ch2,main_addr_ch3,main_addr_ch4,main_addr_ch5,0
+_eop:    .word 0                ; End of program
+.scend
diff --git a/hello_world/hello.oph b/hello_world/hello.oph
index eac7786..7314301 100644
--- a/hello_world/hello.oph
+++ b/hello_world/hello.oph
@@ -1,13 +1,9 @@
-; The 6502 is little endian! (4 3 2 1)
+; Many thanks to:
+; https://michaelcmartin.github.io/Ophis/
+; https://www.nesdev.org/obelisk-6502-guide/addressing.html
+; https://www.masswerk.at/6502/6502_instruction_set.html
 
-; PRG format
-;   Contains two bytes of header data, address from which
-;   the rest of the file will be loaded into memory.
-; BASIC memory starts at addr 2048, we effectively place "10 SYS 2064"
-; and an end of program after it. Then immedately afterwards
-; we place our command on addr 2064.
-;   When BASIC loads up, it runs "10 SYS 2064" and passes up execution there.
-;   Then, when we return, we get a zero which indicates termination.
+; The 6502 is little endian! (4 3 2 1)
 
 ; lables
 ;   [a-z]:  Normal label
@@ -72,43 +68,8 @@
 
 .outfile "hello.prg"
 
-;== Preloader ==;
-
-; The starting address is defined by the value (label or alias) "main".
-; Since in basic we need to provide a decimal string, but we store a decimal value, we need
-; to do this complicated convertion.
-.alias main_addr_ch1 '0 + main / 10000                         ; 65535 -> 6
-.alias main_addr_ch2 '0 + [main - main / 10000 * 10000] / 1000 ; 65535 -> 65535 - 60000 = 5535 / 1000 = 5
-.alias main_addr_ch3 '0 + [main - main / 1000 * 1000] / 100    ; 65535 -> 65535 - 65000 = 535 / 100 = 5
-.alias main_addr_ch4 '0 + [main - main / 100 * 100] / 10       ; 65535 -> 65535 - 65500 = 35 / 10 = 3
-.alias main_addr_ch5 '0 + main - main / 10 * 10                ; 65535 -> 65535 - 65530 = 5
-
-.word $0801 ; Header -- addr 2049
-.org  $0801 ; Program Counter
-
-.scope
-         .word _eop             ; Next line addr  (I guess it is used to tell how long the line is?)
-         .word 10               ; 10              (line of BASIC program)
-         .byte $9e," "          ; SYS 2064        (opcode for SYS and null terminated string)
-         .byte main_addr_ch1,main_addr_ch2,main_addr_ch3,main_addr_ch4,main_addr_ch5,0
-_eop:    .word 0                ; End of program
-.scend
-
-;== Program ==;
-
-; KERNAL
-.alias putchar $FFD2
-
-; PROGRAM
-.macro print
-         ldx #0       ; x = 0
- _loop:  lda _1, x    ; while (_1[x] != 0) {
-         beq _done
-         jsr putchar  ;    putchar(_1[x])
-         inx          ;    ++x
-         jmp _loop    ; }
- _done:
-.macend
+.require "basic_starter.oph"
+.require "kernal.oph"
 
 main:    `print hello
          rts
diff --git a/hello_world/kernal.oph b/hello_world/kernal.oph
new file mode 100644
index 0000000..086d3c1
--- /dev/null
+++ b/hello_world/kernal.oph
@@ -0,0 +1,12 @@
+.alias putchar $FFD2
+
+; print [null-terminated string start address]
+.macro print
+         ldx #0       ; x = 0
+ _loop:  lda _1, x    ; while (_1[x] != 0) {
+         beq _done
+         jsr putchar  ;    putchar(_1[x])
+         inx          ;    ++x
+         jmp _loop    ; }
+ _done:
+.macend