uxn

commit 7ba9782459adba7b3e58f82a7df88da721319980
parent 9597611918e265824bf0e1609266ea006175738a
Author: neauoire <aliceffekt@gmail.com>
Date:   Thu,  4 Feb 2021 15:38:04 -0800

*

Diffstat:
M
README.md
 | 
27
++++++++-------------------
M
uxn.c
 | 
10
++++++++--

2 files changed, 16 insertions(+), 21 deletions(-)
diff --git a/README.md b/README.md
@@ -26,22 +26,20 @@ cc uxn.c -std=c89 -Os -DNDEBUG -g0 -s -Wall -Wno-unknown-pragmas -o uxn
 - `( comment )`
 
 ```
-( comment )
+;value ( alloc zero-page variable )
 
-;variable1
-;variable2
-;variable3
+@0010 ( start at page 1 )
 
-.there ( 0a 05 GTH ) JMC
+,there [ ,0a ,05 GTH ] JMC
 
 :here
-	< when not equal >
-	ee
+	( when not equal )
+	,ee
 	BRK
 
 :there
-	< when is equal >
-	ff
+	( when is equal )
+	,ff
 	BRK
 ```
 
@@ -49,7 +47,6 @@ cc uxn.c -std=c89 -Os -DNDEBUG -g0 -s -Wall -Wno-unknown-pragmas -o uxn
 
 ### Assembler
 
-- Crash on missing label
 - Catch overflow/underflow
 - Constants
 - Jumps should be relative
@@ -58,20 +55,12 @@ cc uxn.c -std=c89 -Os -DNDEBUG -g0 -s -Wall -Wno-unknown-pragmas -o uxn
 
 - Pointers/Literals
 - A Three-Way Decision Routine(http://www.6502.org/tutorials/compare_instructions.html)
-- Carry flag?
 - Print word to stdout
 - Draw pixel to screen
 - Detect mouse click
 - SDL Layer Emulator
 - Build PPU
-- Interrupts, vectors
-
-### 16 Bit Missions
-
-- 16 bits addressing
-- jumping to subroutine should be relative
-- Implement addressing
-- Implement 16 bits operations
+- Add flags..
 
 ## Refs
 
diff --git a/uxn.c b/uxn.c
@@ -165,7 +165,7 @@ error(char *name)
 }
 
 int
-eval()
+eval(void)
 {
 	Uint8 instr = cpu.rom.dat[cpu.rom.ptr++];
 	if(cpu.literal > 0) {
@@ -197,7 +197,13 @@ start(FILE *f)
 	cpu.vreset = mempoke16(0xfffa);
 	cpu.vframe = mempoke16(0xfffc);
 	cpu.verror = mempoke16(0xfffe);
-	while(!(cpu.status & FLAG_HALT) && eval(cpu))
+	/* eval reset */
+	cpu.rom.ptr = cpu.vreset;
+	while(!(cpu.status & FLAG_HALT) && eval())
+		;
+	/*eval frame */
+	cpu.rom.ptr = cpu.vframe;
+	while(!(cpu.status & FLAG_HALT) && eval())
 		;
 	/* debug */
 	printf("ended @ %d steps | ", cpu.counter);