DS80C400 Conitguous Mode Memory Access Error

I am simulating the DS80C400 and have an access error.

Thanks in advance, Clayton.

First off, I am new to Keil and the DS80C400. I am using the eval uVision v2.38a with C51 V7.06, LX51 V3.58 until my real PK51 kit comes in.

The error
*** error 65: access violation at X:0x400003 : no 'write' permission.
This occurs at the line at the location between quotes "<<- PROBLEM ACCESS"
The extsp=0x0003 <- - Is this the problem, I am placing function calling return bytes to exec read territory?
This error occurs at entry point to init_rom() from main().

I used LX51, 16M Continuous Mode Access.
The register ACON=0xFE which is correct.

Main() is close to the end of this email where invokes init_rom()

Am I corrupting the interrupt vectors? I thought I read somewhere that there is an issue with Keil interrupt vectors and DS80C400 interrupt vectors.


(I have a similar problem if I don't use this function init_rom(), where I call a simple function that right upon entering the same access problem happens.)


From the Output Window some diagnostics:

Map
I:0x00 - I:0xFF read write
C:0x000000 - C:0x00FFFF exec read
C:0x400000 - C:0x4004D5 exec read
X:0x000000 - X:0x00FFFF read write
X:0x100000 - X:0x10000F read write
X:0xFFDB00 - X:0xFFFFFF read write

Scope
Tgroup 'unnamed':
Module '?C_STARTUP', source := 'startup400.a51'
Function '?C_CPURESET?0_AP0006_400000', range C:0x400000-C:0x400047
Module 'MAIN', source := 'main.c'
Function 'main', range C:0x400496-C:0x4004D5
Module 'ROM400_LIB_INIT', source := 'rom400_lib_init.a51'
Function '?PR?INIT_VERSION?ROM400_LIB_INIT_AP000F_000000', range C:0x40048D-C:0x400492
Module '?C?LSTXDATA', source := 'unknown'




This is the main() code:

#include "rom400_init.h"
#include <stdio.h>

// leave 4000h bytes for function parameters
#define RAM_START 0x14000
#define RAM_END 0x5FFFF

//void fun1(int x);
//void fun1(void);
/*
 * Main entry point.  Initialize the ROM.
 */
void main()
{
 int data i;
 int data j;

 init_rom(RAM_START, RAM_END);

 i = 0;
 j = 0;

 while(i<4)
 {
  j = j + i;
  i = i + 1;
 }
}


This is the Startup400.A51 and a main() disassembly.



 121: ?C_STARTUP: sjmp  past_loader_tag
 122: db 'TINI'  ; Tag for TINI Environment 1.02c
 123:    ; or later (ignored in 1.02b)
 124: $if (USE_MONITOR = 0)
 125: db  40H  ; Target bank
 126: $endif
 127: $if (USE_MONITOR = 1)
 128: db  20H  ; Target bank
 129: $endif
 130:
 131: past_loader_tag:
C:0x400000  8005 SJMP PAST_LOADER_TAG(C:0007)
C:0x400002  5449 ANL  A,#0x49
C:0x400004  4E ORL  A,R6
C:0x400005  49 ORL  A,R1
C:0x400006  40C2 JC C:FFCA
C:0x400008  AF75 MOV  R7,0x75
C:0x40000A  C7 XCH  A,@R1
C:0x40000B  AA75 MOV  R2,0x75
C:0x40000D  C7 XCH  A,@R1
C:0x40000E  5543 ANL  A,0x43
C:0x400010  9D SUBB A,R5
C:0x400011  020240 LJMP C:0240
C:0x400014  00 NOP
C:0x400015  16 DEC  @R0
 142: mov ta, #0xAA  ; Enable access to MCON
C:0x400016  75C7AA MOV  TA(0xC7),#SADDR1(0xAA)
 143: mov ta, #0x55
C:0x400019  75C755 MOV  TA(0xC7),#0x55
 144: mov mcon, #0xAF  ; Relocate RAM, data memory
C:0x40001C  75C6AF MOV  MCON(0xC6),#C0M5C(0xAF)
 145: mov ta, #0xAA  ; Enable access to ACON
C:0x40001F  75C7AA MOV  TA(0xC7),#SADDR1(0xAA)
 146: mov ta, #0x55
C:0x400022  75C755 MOV  TA(0xC7),#0x55
 147: orl acon, #0x04  ; Extended stack
 148:
 149: ;
 150: ; Make sure we are in a known state with respect to
 151: ; our fancy data pointers and register banks
 152: ;
C:0x400025  439D04 ORL  ACON(0x9D),#0x04
 153: mov dps, #0
C:0x400028  758600 MOV  DPS(0x86),#init_rom?BYTE(0x00)
 154: mov psw, #0
 155:
 156: ;
 157: ; Set stack to 0 (we lose one byte, but don't
 158: ; have to know the size)