这是几年前做的了，一直都不想分享出来，后来想想为了能够给大家点想法，献出来了。。。
这是一个电脑读称的方法，一般用COMM口连接的电子设备都可参考。
如果是对串口参数不确定的，可以网上找个串口测试工具，轻松测出串口参数
网上搜索MSCOMM32.OCX
1.将上面的MSCOMM32.OCX保存到系统目录下C:\Windows\SysWOW64\MSCOMM32.OCX
然后注册：REGSVR32 C:\Windows\SysWOW64\MSCOMM32.OCX
2．修改注册表：
REGEDIT
在HKEY_CLASSES_ROOT\Licenses下建一项：
4250E830-6AC2-11cf-8ADB-00AA00C00905
修改数值数据：kjljvjjjoquqmjjjvpqqkqmqykypoqjquoun
重新启动电脑，这样COMM组件就能使用了
以上是在PC上配置的数据。
登陆GUI
T-code: SOLE
新建条目：
OLE 应用程序 MSCOMMLIB.MSCOMM.1
版本号
类标识 {648A5600-2C6E-101B-82B6-000000000014}
CLSID 库类型
OLE 对象名
类型信息键值
包含程序
语言
检查权限
文本
FUNCTION z_bc_get_balance.
*"----------------------------------------------------------------------
*"*"本地接口：
*" IMPORTING
*" REFERENCE(MODE) TYPE I DEFAULT 0
*" REFERENCE(COMMPORT) TYPE I DEFAULT 1
*" VALUE(SETTINGS) TYPE C DEFAULT '1200,N,8,1'
*" REFERENCE(I_INPUT) TYPE C OPTIONAL
*" EXPORTING
*" REFERENCE(E_OUTPUT) TYPE C
*" EXCEPTIONS
*" NO_CREATE_OBJECT
*"---------------------------------------------------------------------- TYPE-POOLS:sabc.
INCLUDE ole2incl.
DATA pos TYPE i.
CLEAR: pos,balance,value,e_output.
PERFORM prm_get_settings CHANGING settings.
* WAIT UP TO 3 SECONDS.
PERFORM prm_init.
PERFORM prm_open_port USING commport settings.
IF mode = ."读取串口数据
PERFORM prm_read_port CHANGING e_output.
ELSEIF mode = ."写串口数据
PERFORM prm_write_port USING i_input CHANGING e_output.
ENDIF.
PERFORM prm_final.
SEARCH balance FOR '+'.
IF sy-subrc = .
pos = sy-fdpos.
SHIFT balance BY ( pos + ) PLACES.
ENDIF.
SEARCH balance FOR 'g'.
IF sy-subrc = .
pos = sy-fdpos.
balance = balance+(pos).
CONDENSE balance NO-GAPS.
e_output = balance.
ENDIF.
COMMIT WORK
ENDFUNCTION. 此块为配置接口类型模块(自建表用IP地址来配置相应的comm口参数)
*****************************************************************************
FORM prm_get_settings CHANGING p_settings.
DATA addr TYPE ni_nodeaddr.
CLEAR addr.
CALL FUNCTION 'TH_USER_INFO'
IMPORTING
addrstr = addr.
SELECT SINGLE setting INTO p_settings FROM zbctaddr WHERE addr = addr.
IF sy-subrc = .
CLEAR addr.
ENDIF.
ENDFORM. " PRM_GET_SETTINGS 初始化接口对象
******************************************************************************
FORM prm_init .
DATA:
wa_repid LIKE sy-repid.
CLEAR wa_repid.
wa_repid = sy-repid.
CALL FUNCTION 'AUTHORITY_CHECK_OLE'
EXPORTING
program = wa_repid
activity = sabc_act_call
application = 'MSCOMMLIB.MSCOMM.1'
EXCEPTIONS
no_authority =
activity_unknown =
OTHERS = .
IF sy-subrc <> .
MESSAGE ID sy-msgid TYPE sy-msgty NUMBER sy-msgno
WITH sy-msgv1 sy-msgv2 sy-msgv3 sy-msgv4.
ENDIF.
CREATE OBJECT o_obj 'MSCOMMLib.MSComm.1'.
IF sy-subrc <> .
RAISE no_create_object.
ENDIF.
ENDFORM. " PRM_INIT 接口打开
***************************************************************************
FORM prm_open_port USING commport
settings. SET PROPERTY OF o_obj 'CommPort' = commport.
SET PROPERTY OF o_obj 'Settings' = settings.
SET PROPERTY OF o_obj 'InputLen' = .
SET PROPERTY OF o_obj 'PortOpen' = .
ENDFORM. " PRM_OPEN_PORT 读取接口数据：因为接口有缓存所以每次读取时都是去掉前面20次的数据
而且每次读取的数据都是不完整的，所以需要将多次读取的数据连接起来，然后截取
****************************************************************************
FORM prm_read_port CHANGING e_output.
DATA:
wa_buffer TYPE i,
inde TYPE i.
DO TIMES.
inde = inde + .
GET PROPERTY OF o_obj 'InBufferCount' = wa_buffer.
IF wa_buffer > .
GET PROPERTY OF o_obj 'Input' = e_output.
IF inde < .
ELSE.
CONCATENATE balance e_output INTO balance.
ENDIF.
ENDIF.
ENDDO.
CLEAR:wa_buffer,inde.
ENDFORM. " PRM_READ_PORT 往串口写数据，因为没有需求所以没做测试
*********************************************************************
FORM prm_write_port USING i_input
CHANGING e_output.
DATA:
wa_buffer TYPE i.
SET PROPERTY OF o_obj 'Output' = i_input.
DO TIMES.
GET PROPERTY OF o_obj 'InBufferCount' = wa_buffer.
IF wa_buffer > .
GET PROPERTY OF o_obj 'Input' = e_output.
EXIT.
ENDIF.
ENDDO.
ENDFORM. " PRM_WRITE_PORT 读数结束，关闭串口，释放对象，清空变量
************************************************************************
FORM prm_final .
SET PROPERTY OF o_obj 'PortOpen' = .
FREE OBJECT o_obj.
CLEAR o_obj.
COMMIT WORK.
ENDFORM. " PRM_FINAL
对读数做了个简单的处理
FORM PRM_READ_PORT02 CHANGING E_OUTPUT.
DATA:
WA_BUFFER TYPE I,
INDE TYPE I,LV_CHAR TYPE C.
DATA:LV_STR TYPE STRING VALUE '0123456789.'.
DATA:LV_STR2 TYPE STRING.
DATA:LV_STR3 TYPE STRING.
DATA POS TYPE I.
CLEAR:LV_CHAR,LV_STR2,INDE,LV_STR3,POS.
WHILE LV_CHAR IS INITIAL.
GET PROPERTY OF O_OBJ 'InBufferCount' = WA_BUFFER.
IF WA_BUFFER > . GET PROPERTY OF O_OBJ 'Input' = E_OUTPUT.
SEARCH E_OUTPUT FOR '+'.
IF SY-SUBRC = .
POS = SY-FDPOS.
SHIFT E_OUTPUT BY ( POS + ) PLACES.
ELSE.
CONTINUE.
ENDIF. SEARCH E_OUTPUT FOR 'g'.
IF SY-SUBRC = .
POS = SY-FDPOS.
E_OUTPUT = E_OUTPUT+(POS).
CONDENSE E_OUTPUT NO-GAPS.
E_OUTPUT = E_OUTPUT.
ELSE.
CONTINUE.
ENDIF. * SEARCH E_OUTPUT FOR '.'.
* IF SY-SUBRC = 0.
* ELSE.
* CONTINUE.
* ENDIF
*.
CLEAR:LV_STR2.
MOVE E_OUTPUT TO LV_STR2.
IF LV_STR2 CO LV_STR.
* INDE = INDE + 1.
* IF INDE = 1.
* MOVE E_OUTPUT TO LV_STR3.
* ELSEIF INDE = 2.
* CLEAR:INDE.
* IF LV_STR2 = LV_STR3.
LV_CHAR = 'X'.
* ENDIF.
* ENDIF.
ENDIF.
ENDIF.
ENDWHILE.
CLEAR:WA_BUFFER,INDE.
ENDFORM. " PRM_READ_PORT02
以字符流传过来的，在处理的时候，自己看着办了。。。