Moved additional zeropage variables into an extra module.

[cc65] / doc / internal.txt

diff --git a/doc/internal.txt b/doc/internal.txt
index 2c2476f6ae08ec717f20979dd1bdcd0870b9567f..fdda2359e13de4e84af7f6959c22130fccab69bd 100644 (file)
--- a/doc/internal.txt
+++ b/doc/internal.txt
@@ -13,10 +13,8 @@ data etc are allocated on this stack, and deallocated when functions exit.
 
 The program code and data is located in low memory. The heap is located
 between the program code and the stack. The default size for the parameter
-stack is 2K, you may change this by declaring an externally visible variable
-named named _stksize that holds the new stack size:
-
-    unsigned _stksize = 4*1024;                /* Use 4K stack */
+stack is 2K, you may change this for most platforms in the linker
+configuration.
 
 Note: The size of the stack is only needed if you use the heap, or if you
 call the stack checking routine (_stkcheck) from somewhere in your program.
@@ -112,9 +110,18 @@ compiling them into assembler.  Therefore if you have a C function named
 Systems:
 --------
 
-Supported systems at this time are: C64, C128, Plus/4, CBM 600/700, the newer
-PET machines (not 2001), Atari 8bit, and the Apple ][ (thanks to Kevin Ruland,
-who did the port).
+Supported systems at this time are: C64, C128, Plus/4, CBM 500, CBM 600/700,
+the newer PET machines (not 2001), Atari 8bit, and the Apple ][ (thanks to
+Kevin Ruland, who did the port).
+
+C16:    Works with unexpanded or memory expanded C16 and C116 machines.
+        However, a maximum of 32KB from the total memory is used. The Plus/4
+        target supports up to 64K of memory, but has a small code overhead
+        because of the banking routines involved. Apart from this additional
+        overhead, the Plus/4 target and the C16 target are the same. 16K
+        machines (unexpanded C16) have 12K of memory for C programs available,
+        machines with 32K or more have 28K available. The actual amount of
+        memory is auto detected.
 
 C64:   The program runs in a memory configuration, where only the kernal ROM
        is enabled. The text screen is expected at the usual place ($400), so
@@ -129,6 +136,12 @@ Plus/4:    Unfortunately, the Plus/4 is not able to disable only part of it's
                has only 28K available (16K machines are detected and the amount of
        free memory is reduced to 12K).
 
+CBM 500:
+       The C program runs in bank #0 and has a total of 48K memory available.
+       This is less than what is available on its bigger brothers (CBM
+       600/700) because the character data and video RAM is placed in the
+       execution bank (#0) to allow the use of sprites.
+
 CBM 600/700:
        The C program runs in a separate segment and has almost full 64K of
        memory available.
@@ -175,10 +188,7 @@ assembler file.
 
 Example, insert a break instruction into the code:
 
-               asm ("\t.byte\t$00")
-
-Note: The \t in the string is replaced by the tab character, as in all other
-strings.
+               asm ("brk")
 
 Beware: Be careful when inserting inline code since this may collide with
 the work of the optimizer.
@@ -197,7 +207,9 @@ functions results and pass parameters.
 This feature is useful with inline assembly and macros. For example, a macro
 that reads a CRTC register may be written like this:
 
-#define wr(idx) (__AX__=(idx),                                 \
-               asm("\tsta\t$2000\n\tlda\t$2000\n\tldx\t#$00"), \
+#define wr(idx) (__AX__=(idx),                 \
+                       asm ("sta $2000"),      \
+                asm ("lda $2000"),      \
+                asm ("ldx #$00"),      \
                __AX__)