7 files changed, 100 insertions, 60 deletions
diff --git a/asm/ext_string_io.py b/asm/ext_string_io.py
new file mode 100644
index 0000000..cf7d598
--- /dev/null
+++ b/asm/ext_string_io.py
@@ -0,0 +1,47 @@
+from asm_ops import *
+from ext_std import expand_addi
+
+def to_char_code(c: str):
+  if c == " " or c == "%SPACE": return 0
+  else: return ord(c) - 64
+
+_counter = 0
+def get_unique_name(prefix: str):
+  global _counter
+  ret =  f"{prefix}_{_counter}"
+  _counter += 1
+  return ret
+
+def expand_put_char(cursor_reg: str, scratch_reg: str, c: str) -> ExpandResult:
+  return [
+    ["ldi", str(to_char_code(c)), scratch_reg],
+    ["str", scratch_reg, cursor_reg],
+    *expand_addi("RA", "1", "RA"),
+  ]
+
+def expand_put_string(cursor_reg: str, scratch_reg: str, *rest: str) -> ExpandResult:
+  string = " ".join(rest)
+  result: ExpandResult = []
+  for c in string:
+    result += expand_put_char(cursor_reg, scratch_reg, c)
+
+  return result
+
+def expand_cursor_to_line(cursor_reg: str, line: int) -> ExpandResult:
+  lbl_data = get_unique_name("cursor_to_line_data")
+  lbl_jmpover = get_unique_name("cursor_to_line_jmpover")
+  line_width = 64
+  return [
+    ["jpi", lbl_jmpover],
+    ["@label", lbl_data],
+    [f"text_mem + {line} * {line_width}"],
+    ["@label", lbl_jmpover],
+    ["ldi", lbl_data, cursor_reg],
+    ["ldr", cursor_reg, cursor_reg],
+  ]
+
+expansions: OpExpansionDict = {
+  "put_char": expand_put_char,
+  "cursor_to_line": expand_cursor_to_line,
+  "put_string": expand_put_string,
+}
+\ No newline at end of file
diff --git a/asm/text_mode.atk16 b/asm/text_mode.atk16
index ff84156..f4d84ae 100644
--- a/asm/text_mode.atk16
+++ b/asm/text_mode.atk16
@@ -1,61 +1,19 @@
 @opt stack_pointer RF
 @opt csr_scratch RH
 @use ext_std:*
+@use ext_string_io:*
 
 ; bootstrap code (must be called to set up mandatory data)
 ; will jump to label main
 @include bootstrap
 
 @label main
-  ldi vt_text_mem RA
-  ldr RA RA
-  ldi 8 RB   ; letter H
-  str RB RA
-  addi RA 1 RA
-  ldi 5 RB   ; letter E
-  str RB RA
-  addi RA 1 RA
-  ldi 12 RB  ; letter L
-  str RB RA
-  addi RA 1 RA
-  ldi 12 RB  ; letter L
-  str RB RA
-  addi RA 1 RA
-  ldi 15 RB  ; letter O
-  str RB RA
-  addi RA 1 RA
-  ldi 0 RB   ; space
-  str RB RA
-  addi RA 1 RA
-  ldi 3 RB   ; letter C
-  str RB RA
-  addi RA 1 RA
-  ldi 15 RB  ; letter O
-  str RB RA
-  addi RA 1 RA
-  ldi 18 RB  ; letter R
-  str RB RA
-  addi RA 1 RA
-  ldi 5 RB  ; letter E
-  str RB RA
-  addi RA 1 RA
-  ldi 3 RB  ; letter C
-  str RB RA
-  addi RA 1 RA
-  ldi 1 RB  ; letter A
-  str RB RA
-  addi RA 1 RA
-  ldi 13 RB  ; letter M
-  str RB RA
-  addi RA 1 RA
-  ldi 16 RB  ; letter P
-  str RB RA
-  ldi offset RC
-  ldr RC RC
-  add RA RC RA
-  ; ldi 20 RB   ; letter A
-  ; str RB RA
-  ; addi RA 1 RA
+  cursor_to_line RA 1
+  put_char RA RB %SPACE
+  put_string RA RB HELLO CORECAMP
+  cursor_to_line RA 3
+  put_char RA RB %SPACE
+  put_string RA RB BY JAN
 
   ; set graphics mode to sprite mode
   ; set_graphics_mode gr_sprite_mode
@@ -63,6 +21,3 @@
 
 @label loop
   jpi loop
-
-@label offset
-  51
diff --git a/digital/atk16_mem.dig b/digital/atk16_mem.dig
index c3663e3..31fe276 100644
--- a/digital/atk16_mem.dig
+++ b/digital/atk16_mem.dig
@@ -37,11 +37,13 @@
           <string>Data</string>
           <data>4014,2a00,6029,13*8000,1c,1a,1a,1a,8000,e000,e001,e002,e800,f800
 ,4855,f000,3140,1b48,3148,1b48,4016,2000,2000,4215,2240,3040,1800
-,3148,1b48,3140,1b48,e000,4017,2000,4200,3008,6000,4019,2000,4208
-,3008,1008,4205,3008,1008,420c,3008,1008,420c,3008,1008,420f,3008
-,1008,4200,3008,1008,4203,3008,1008,420f,3008,1008,4212,3008,1008
-,4205,3008,1008,4203,3008,1008,4201,3008,1008,420d,3008,1008,4210
-,3008,4464,2480,10,4017,2000,4201,3008,61ff,33</data>
+,3148,1b48,3140,1b48,e000,4017,2000,4200,3008,6000,6001,f840,4032
+,2000,4200,3008,1008,4208,3008,1008,4205,3008,1008,420c,3008,1008
+,420c,3008,1008,420f,3008,1008,4200,3008,1008,4203,3008,1008,420f
+,3008,1008,4212,3008,1008,4205,3008,1008,4203,3008,1008,4201,3008
+,1008,420d,3008,1008,4210,3008,1008,6001,f8c0,4063,2000,4200,3008
+,1008,4202,3008,1008,4219,3008,1008,4200,3008,1008,420a,3008,1008
+,4201,3008,1008,420e,3008,1008,4017,2000,4201,3008,61ff</data>
         </entry>
       </elementAttributes>
       <pos x="740" y="100"/>
diff --git a/src/asm_pass0.py b/src/asm_pass0.py
index 4913e4b..f5b6b0b 100644
--- a/src/asm_pass0.py
+++ b/src/asm_pass0.py
@@ -2,6 +2,7 @@ from dataclasses import dataclass
 import os.path
 from asm_ops import *
 from asm_eval import *
+from tokenizer import *
 
 @dataclass
 class Result0Line:
@@ -19,7 +20,9 @@ def pass_0(lines: list[str], file_name: str) -> Result0:
   for (line_num, line) in enumerate(lines):
     line = line.split(";")[0].strip()
     if line == "": continue
-    keyword, *args = line.lower().split()
+
+    keyword, *args = tokenize(line)
+
     match keyword:
       case "@include":
         asm_file_name = args[0]
diff --git a/src/asm_pass1.py b/src/asm_pass1.py
index d462526..5e6213a 100644
--- a/src/asm_pass1.py
+++ b/src/asm_pass1.py
@@ -5,6 +5,7 @@ from dataclasses import dataclass
 from asm_ops import *
 from asm_eval import *
 from asm_pass0 import *
+from tokenizer import tokenize
 
 @dataclass
 class Result1Line:
@@ -24,7 +25,7 @@ def pass_1(result0: Result0) -> Result1:
   operations: OpExpansionDict = default_expansions.copy()
 
   for line in result0.lines:
-    keyword, *args = line.line.lower().split()
+    keyword, *args = tokenize(line.line)
     match keyword:
       case "@opt":
         opt_name, opt_value = args
diff --git a/src/charmem.py b/src/charmem.py
index 9b19864..551ba85 100644
--- a/src/charmem.py
+++ b/src/charmem.py
@@ -43,7 +43,7 @@ def string_to_byte(input_string: str):
 
     # Check if the string contains only '0' or '1'
     if not all(c in '01' for c in binary_string):
-        raise ValueError("Input string must contain only spaces and '#' characters.")
+        raise ValueError("Input string must contain only spaces and '█' characters.")
 
     # Convert the binary string to an unsigned integer byte
     return int(binary_string[::-1], 2)
diff --git a/src/tokenizer.py b/src/tokenizer.py
new file mode 100644
index 0000000..2049461
--- /dev/null
+++ b/src/tokenizer.py
@@ -0,0 +1,32 @@
+def tokenize(line: str) -> list[str]:
+  cur: str = ""
+  result: list[str] = []
+  is_py_expr = False
+  idx = 0
+  while idx < len(line):
+    c = line[idx]
+    if not is_py_expr and c == "$":
+      is_py_expr = True
+      idx += 1
+    elif is_py_expr and c == "$":
+      raise Exception("Unexpected start of python expr while already parsing a python expression:\n" + line)
+    elif not is_py_expr and c == "}":
+      raise Exception("Unexpected end of python expr while not parsing a python expression:\n" + line)
+    elif is_py_expr and c == "}":
+      is_py_expr = False
+      result.append(cur)
+      cur = ""
+    elif is_py_expr:
+      cur += c
+    elif c == " " or c == "\t":
+      result.append(cur)
+      cur = ""
+    else:
+      cur += c
+
+    idx += 1
+
+  if len(cur) > 0:
+    result.append(cur)
+
+  return [r for r in result if r != ""]
+\ No newline at end of file