keil设置

使用单片机编程的朋友们都知道，常规的51系列单片机地址寻址空间只有64K，如果程序编写超过64K，那么只好通过增加外部程序存储器来实现目标，但是如果这样做无疑增加了硬件成本，单片机生产商为了解决这个问题，现在已经开发出可寻址128K、256K，甚至更大ROM的单片机。  
     但是熟知keil的人都知道，keil默认64K寻址，如果想要做超过64K的程序该如何设置呢？这就要利用keil开发出来的BL51功能，下面以芯唐单片机W77E532为例进行介绍，具体操作步骤如下：  
    首先打开keil并选择要使用的芯片，如W77E532，之后点击“USE EXTENDED LINKER(LX51) INSTEAD OF BL51”为选中状态；之后设置点击“TARGET”设置晶振频率和memory model为small、code rom size为large、operating为none，该窗口下面的“code banking”选中，同时设置bank分区，如W77E532为2，后面的START和END可以设置成0x0000和0xFFFF；接下来设置“OUTPUT”点击“Create HEX Fi：”从后面的下拉列表中选择“HEX-386”，这些全部设置完成后点击“确定”以完成设置。 
        接下来开始设置工程信息，点击菜单栏中的“project”并选择下面的“Components，Environment，Books…”项，在group中添加3个分区的文件目录，依次为root，bank和bank1， 
之后在各个目录下面添加属于该目录的文件， 
设置完成后点击“确定”保存。 
      当这些都设置完成后，在左侧“project workspace”区域对root，bank和bank1的code bank和stop on exit分别设置，依次为: 
common和translator fatal errors (exit code >=3)， 
bank#0和translator fatal errors (exit code >=3)， 
bank#1和translator fatal errors (exit code >=3)； 
之后对各个目录右侧进行设置，只选择“include in target build”，其余为空状态，点击“确定”完成设置。  
      注意在root目录中必须有L51_BANK.A51和STARTUP.A51存在，而L51_BANK.A51文件根据用户使用进行实际配置，配置区域如下： 
NOMOD51NOLINESNOCOND 
;—————————————————————————— 
;  This file is part of the BL51 / LX51 Banked Linker/Locater package 
;  Copyright (c) 1988 - 2005 Keil Elektronik GmbH and Keil Software, Inc. 
;  Version 2.21 (Code and Variable Banking for Classic 8051 Derivatives) 
;—————————————————————————— 
;************** Configuration Section ********************* 
?B_NBANKS       EQU  2    ; Define maximum Number of Banks                    * 
;                         ; following values are allowed: 2, 4, 8, 16, 32, 64 * 
;                         ; for BL51 the maximum value for ?B_BANKS is 32     * 
;                         ; for LX51 the maximum value for ?B_BANKS is 64     * 
;                                                                             * 
?B_MODE         EQU  0    ; 0 for Bank-Switching via 8051 Port                * 
;                         ; 1 for Bank-Switching via XDATA Port               * 
;                         ; 4 for user-provided bank switch code              * 
;                                                                             * 
?B_RTX          EQU  0    ; 0 for applications without real-time OS           * 
;                         ; 1 for applications using the RTX-51 real-time OS  * 
;                                                                             * 
?B_VAR_BANKING  EQU  1    ; Variable Banking via L51_BANK (far memory support)* 
;                         ; 0 Variable Banking does not use L51_BANK.A51      * 
;                         ; 1 Variable Banking uses this L51_BANK.A51 module  * 
; Notes: ?B_VAR_BANKING uses the ‘far’ and ‘far const’ C51 memory types to    * 
;        extent the space for variables in RAM and/or ROM of classic 8051     * 
;        device.  The same hardware as for code banking is used.  Program     * 
;        code banking and variable banking share the same hardware I/O pins.  * 
;        The C51 Compiler must be used with the VARBANKING directive.         * 
;        Variable Banking is only supported with the LX51 linker/locater.     * 
;                                                                             * 
?B_RST_BANK     EQU  0    ; specifies the active code bank number after CPU   * 
;                         ; Reset.  Used to reduce the entries in the         * 
;                         ; INTERBANK CALL TABLE.  The value 0xFF disables    * 
;                         ; this LX51 linker/locater optimization.            * 
; Note:  Interbank Call Table optimization is only possible with LX51.        * 
;                                                                             * 
;—————————————————————————–* 
;                                                                             * 
IF  ?B_MODE = 0;                                                              * 
;—————————————————————————–* 
; if ?BANK?MODE is 0 define the following values                              * 
; For Bank-Switching via 8051 Port define Port Address / Bits                 * 
;                                                                             * 
P1              DATA    90H      ; I/O Port Address                           * 
;                                                                             * 
?B_PORT         EQU     P1       ; default is P1                              * 
?B_FIRSTBIT     EQU     7        ; default is Bit 2                           * 
;—————————————————————————–* 
ENDIF; 
以上部分需要用户根据分区数量和用途自行设置。 
注意：root和bank可以看做在一个分区，初始化的时候将这两个目录分在一起，bank1要靠root选择，一般使用P1口的后面几个引脚做分区使用，不能外接设备。