摘要：DS80C400微控制器ROM的功能可由8051汇编语言、C或Java™编写的程序访问。通过使用ROM功能和由Dallas Semiconductor开发的软件库能够构建多种应用程序。本应用笔记阐述了如何使用8051 IAR Embedded Workbench™来建立DS80C400的C语言应用程序。通过一个简单的HTTP服务器示例来演示DS80C400的ROM功能。
本应用笔记阐述了如何开始使用8051 IAR Embedded Workbench™来创建DS80C400的C语言应用程序。通过一个简单的HTTP服务器演示如何使用DS80C400的ROM功能。所有开发都采用TINIm400验证模块和包含6.11A版本C编译器的8051 IAR Embedded Workbench。
DS80C400 Silicon Software - Copyright (C) 2002 Maxim Integrated Products
Detailed product information available at http://www.maxim-ic.com
Welcome to the TINI DS80C400 Auto Boot Loader 1.0.1
>
接下来的一行用来设置请求选项。在RFC 1361的第3节对这些位进行了说明。0x23在一个闰秒不产生告警，要求使用版本4 NTP，并声明模式为Client。我们使用普通数据包函数sendto和recvfrom请求发送并接收响应后，将时间标记的秒赋予变量timeStamp，然后调整至参考日期1970年1月1号。用函数formatTimeString将时间标记转换成一个可读字符串，比如说"In London it is 05:33:19 on May 11, 2005"。
struct sockaddr local;
unsigned int socket_handle, new_socket_handle, temp;
socket_handle = socket(0, SOCKET_TYPE_STREAM, 0);
local.sin_port = htons(80);
bind(socket_handle, &local, sizeof(local));
listen(socket_handle, 5);
printf("Ready to accept HTTP connections...\r
");
// here is the main loop of the HTTP server
while (1)
{
new_socket_handle = accept(socket_handle, &address, sizeof(address));
handleRequest(new_socket_handle);
closesocket(new_socket_handle);
}
--------------------------------------------------------------------------------------------------------------------
Program output:
Set values: int= 0xdead long = 0x12345678
Converted values: int= 0xedde long = 0x78563412
-------------------------------------------------------------------------------------------------------------------
// program main.c
#include <stdio.h>
#include <printf.c>
#include <frmwri.c>
int ltob(unsigned int *intptr,unsigned long *longptr);
void main()
{
unsigned long i = 0x12345678;
unsigned int k = 0xdead;
int err;
printf("set values: int=0x%x long=0x%lx
",k,i);
err = ltob(&k,&i);
if(err)
printf("Error: One of the pointers is NULL
");
else
printf("converted values: int=0x%x long=0x%lx
",k,i);
while(1)
;
}
#include "reg400.inc"
r0_b0 equ 0 ; Register bank 0 equates.
r1_b0 equ 1
r2_b0 equ 2
r3_b0 equ 3
r4_b0 equ 4
r5_b0 equ 5
r6_b0 equ 6
r7_b0 equ 7
PROGRAM ENDIAN_SWAP
PUBLIC ltob
RSEG FAR_CODE:CODE:NOROOT(0)
; ********************************************************************
;
; int ltob(unsigned int* shortptr, unsigned long* longptr)
;
; ********************************************************************
ltob:
// shortptr is in r3:r2:r1
// longptr is in stack at offset 5
; get the longptr stored in the stack
mov a,SP
clr c
subb a,#5
mov b,a
mov a,esp
anl a,#0x3
orl a,#0xDC ; extended stack is at 0xff dc00
subb a,#00 ; subtract 0x0005 to point to MSB of 2 nd argument
mov DPX,#0xFF
mov DPH,a
mov DPL,b
push r6_b0 ; save r6:r7 for the compiler
push r7_b0
movx a,@DPTR
mov r4,a ;store least significant byte of 'longptr' in r4
inc DPTR
movx a,@DPTR
mov r5,a ;store middle byte of 'longptr' in r5
inc DPTR
movx a,@DPTR
mov r6,a ;store most significant byte of 'longptr' in r6
mov a,r4_b0
orl a,r5_b0
orl a,r6_b0
jz ltob_err ; is (longptr == NULL)?
mov dpx,r6_b0 ; point to the memory where 'longptr' is pointing to
mov dph,r5_b0
mov dpl,r4_b0
pop r6_b0 ; restore r6:r7 for the compiler
pop r7_b0
push dpx
push dph
push dpl
movx a,@dptr ; get the long value (in r4:r3:r2:r1) from the memory
mov r4,a
inc dptr
movx a,@dptr
mov r5,a
inc dptr
movx a,@dptr
mov r6,a
inc dptr
movx a,@dptr
mov r7,a
inc dptr
pop dpl
pop dph
pop dpx
mov a,r7_b0 ; swap the long value bytes and store it in memory
movx @dptr,a
inc dptr
mov a,r6_b0
movx @dptr,a
inc dptr
mov a,r5_b0
movx @dptr,a
inc dptr
mov a,r4_b0
movx @dptr,a
mov a,r1_b0 ; is (shortptr == NULL)?
orl a,r2_b0
orl a,r3_b0
jz ltob_err
mov dpx,r3_b0 ; point to a memory where the 'shortptr' is pointing to
mov dph,r2_b0
mov dpl,r1_b0
push dpx
push dph
push dpl
movx a,@DPTR ; get the integer value from memory
mov r2,a
inc dptr
movx a,@dptr
mov r1,a
inc dptr
pop dpl
pop dph
pop dpx
mov a,r1_b0 ; swap the integer bytes
movx @dptr,a
inc dptr
mov a,r2_b0
movx @dptr,a ; bytes of an integer are swapped and stored in memory
mov r3,#00 ; return 'success'
mov r2,#00
sjmp ltob_exit
ltob_err:
mov r3,#00 ; return 'error'
mov r2,#01
ltob_exit:
ret
END ; end of assembly program
IAR编译器用堆栈存储本地变量。在DS80C400中，堆栈限制为1024字节。DS80C400库的默认堆栈交换为384字节(ROM_SAVESIZE) 。如果您的程序声明了多个堆栈变量，确保该限制也适当地变化。要改变默认任务的交换大小，使用Dallas Semiconductor的task_genesis(unsigned int savesize)库或rom400_task.h中定义的task_fork(unsigned char priority, unsigned int savesize)，并给savesize参数提供正确的值。
下载，PDF格式
New
