Post by thread:[PIC]:[EE]: Using Microsoft Access with RS232

I have a project where I would very much like to interface serial port control with Access. I have to transmit a few control words to a bit banged PIC device, and then receive several strings from it after a spell. I use RX and TX for communication and RTS to hard reset the PIC device. Of course these signals go through a MAX232 translator. I have a C program that handles this fine, but I want to integrate this functionality into Access. Access doesn't seem to have the Visual Basic objects for serial communication, nor does it allow calls to DLLs. It can however do calls to ActiveX controls or by way of a DDE link. Very convoluted me thinks, but that is Microsoft for ya! Has anyone done this before? I've seen a few shareware methods, but they are quite foreign to me. ie. Poor detail. I'd prefer the ActiveX method, or something that doesn't require me to build a complete DDE app just to make a couple of serial calls. Help? Craig > {Original Message removed}

You can find activeX wrappers for microsoft's MSCOMM control, which is included in professional and enterprise versions of VB (4 and up). You should be able to peek around and find one of these wrappers, ask in an Access newsgroup. If you know C and have visual C++, then it shouldn't be difficult to write an activeX module to do what you want. -Adam Craig Lee wrote: {Quote hidden}> > I have a project where I would very much like to interface serial port > control with Access. > > I have to transmit a few control words to a bit banged PIC device, and > then receive several strings from it after a spell. I use RX and TX > for communication and RTS to hard reset the PIC device. Of course these > signals go through a MAX232 translator. > > I have a C program that handles this fine, but I want to integrate this > functionality into Access. Access doesn't seem to have the Visual Basic > objects for serial communication, nor does it allow calls to DLLs. It can > however do calls to ActiveX controls or by way of a DDE link. Very > convoluted me thinks, but that is Microsoft for ya! > > Has anyone done this before? I've seen a few shareware methods, but they > are quite foreign to me. ie. Poor detail. I'd prefer the ActiveX method, > or something that doesn't require me to build a complete DDE app just to > make a couple of serial calls. > > Help? > > Craig > > > {Original Message removed}

There are multiple ways of creating an ActiveX object for your Access app to call. It all depends on your programming skill set and tools available to you. These are the solutions that I suggest, in order of preferred (at least to me): 1) If you have source code for the C program and a copy of MS Visual Studio, I would create a simple ATL (Active Template Library) Project with one or more Simple ATL Objects in it that would call or implement the code from the original C program. This is not the simplest approach, but it would offer a dll that was small with little or no dependants. There are a lot of examples of creating ATL DLL's on various sites. 2) Same as above, but use MFC instead of ATL. The resulting DLL will be bigger, but the coding is easier if you don't know ATL. 3) You can create a VB ActiveX DLL or OCX that either calls a native 'C' DLL directly or uses various VB techniques to access the COM port. This is simpler if you know VB and don't know C++/MFC/ATL. There will be more baggage (required DLL's) with this approach. There are more ways, but these three make the most sense from a programmers point of view. If you tell me the Name of the DLL, it's interface and the name/parameters (with data types) of the functions / properties, I could send you a shell ATL project where you would only have to add application specific code. Hope this helps a little. David. -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.

I should indicate that I've seen *free* activeX wrappers for the mscomm control. You shouldn't pay for that. You should really check out either the VB newsgroups or the Access newsgroups. Otherwise there are many people who sell such software... I wouldn't bend over just yet unless you see yourself needing Visual C later -Adam Craig Lee wrote: {Quote hidden}> > I use Borland C. Thanks for the tips, etc. > > I've never used Visual Basic, and I haven't used the ACL stuff > under Visual C... I guess I'm a bit proud in that I despise such convoluted > types, and haven't put in the effort to get my head wrapped around it. > > I haven't used Access either, however I don't need to, all I need to do is > find something that will work with it. > > If someone has an ActiveX Dll with rudimentary functions for control of > serial streams and direct access to RTS/CTS, this is all I need. Maybe we > can trade something? > > I can probably change the PIC protocol a bit so that the RTS control is > no longer necessary. > > Or perhaps I should buy a copy of Visual C and bend over for Billy. > > Thx, > > Craig > > > {Original Message removed}

Craig Lee <spam_OUTpicmeTakeThisOuTENLIGHT.CA> wrote: >I have a C program that handles this fine, but I want to integrate this >functionality into Access. Access doesn't seem to have the Visual Basic >objects for serial communication, nor does it allow calls to DLLs. It can >however do calls to ActiveX controls or by way of a DDE link. - Graig, I have done about similar to my home data collection system, PIC cloud (=lot of PIC's in same environment, also in the my roof). Maybe this is not the right answers for you, but maybe you can learn something. 1 Hardware I have several PIC serial sensor devices for -wind speed -wind direction -oil burner temperature 1 hot water 2 water to radiators, 3 water from radiator -outside temperature 1 ( north) ,2 ( south) -outside light ( north side) -humidity 1 outside, 2 inside All the PIC Cloud members use similar serial commands 2400 bps e.g. #TT00 for temp 00 They respond like $TT00+23.1<CR>. A sensors can be remotely calibrated to EEPROM and their address can be changed. A software filters messages. I normally use 5 measurement per second speed. I call that as a smarTBus protocol. All sensors are connected in parallel to RS232, but they have functional networks address like in CAN-bus. All sensor cables are connected to outside connection box (a cloud box) with has a led +220R series resistor to sensor power supply to protect, isolate and indicate sensor electronics and wiring. The cloud box is installed to height of my head for easy checking wiring. It has transparent, waterproof top cover. It has also a protected 12 V 2A power supply for whole system with 3 LEDs in a different parts of power supply for easy viewing power problems ( in winter we have sometimes -30 ,.. -40 centigrade outside). The whole PIC cloud sensor system works with 2-4 ma coming from PC RS232 DTR/RTS-pin, but I need more power for coming controls. A big 150 mm *400 mm LED display panel is ready for use, but not yet installed. This will be working when PC is off. A PC is connected to one RJ-45 cable slot. The PC sends commands for each sensors according timing from database. 2 Wiring I use 8 pin RJ-45 cheapernet wiring cable and RJ-45 connection boxes for easy fault isolation although 4 wires for a sensor is needed ( power, rx, tx, gnd). A 2-slot RJ-45 box is in a heating room and other 4 box inside near cloud box. wiring from roof ( wind sensor) uses 4 wire telephone cable for its light weight. 3. Software The idea for software has been hard part. How to collect data? How much is needed? What to do when hard disk is full of second data? How to display old data. How to control setups? A relational database is answer for me I use Access 2000 database through ODBC32 connection, ADO 2.5 ( MS ActiveX-data component) driver for VB6.0. 4. Database Weather.mdb database has tables for seconds, minutes, hours, days, months and years When 60 seconds has elapsed I mode data to minutes table and so on. the database can located anywhere in networks. ODBC32 (WIN98/Setup/Odbc32) manages its location. no programming involved. Database length can be adjusted dynamically by user, e.g. 1200 months (10 years is enough for me) Database information length can be adjusted by user. Data of the database is shown in real-time graphics (MSgraph component) all the time. Graphics data can be selected by user ( sensors, trends, grids, scales etc.) The Weather.exe has a digital (current min, max., max. times etc.) and analog display ( easy wind directions). Setup and database editing grid is dome using standard VB 6.0 tools. 5. Sensor setup database First I used Windows registry for display, database and calibration data. It became quite huge and it was difficult to manipulate. Now I have setup database wsetup.mdb, which has all sensor data, commands, timing, calibrations etc. for easy user access. --- Wiring and cloud box take 1-2 days to build and install, software I started about first of June 2000. Most of sensors were almost ready from my normal work. The most difficult thing was to get right software idea. It has no practical use, only a fun project. Pekka -- ¤º°`°º¤ø,¸¸,ø¤º°`°º¤ø,¸¸,ø Pekka Ritamaki, Probyte Oy Microprocessor software & hardware design Nirvankatu 31, 33820 TAMPERE, FINLAND http://www.sci.fi/~pri tel: Int. 358-3-2661885 fax: Int. +358-3-2661886 email:.....priKILLspam@spam@sci.fi -- http://www.piclist.com hint: To leave the PICList piclist-unsubscribe-requestKILLspammitvma.mit.edu>

Pekka, To much sunlight this time of year? Access 2000 is the intended target. It is still not clear how you do the serial access. What is ADO2.5? I tried using MSCOMM32.OCX, I was surprised it was already installed in my system directory. However, each time I go to use it, it says it is improperly registered, or I don't have a license to use it. Screwey! The application is my street racing control system. The pic takes care of the timing and control of the street light. Then when the break beam detectors are tripped, those times are recorded, and sent back to the PC in milliseconds format. Currently, I have a program that does all that control and recording. Then it spits out a text file which is imported into an Access 2000 application and processed to determine classes (bike, big block, small block, tricycle, male, female, fastest reaction time, etc) and find who the winner is in each class. I want to integrate the functionality of my external program into Access, but am having trouble with this task. Do you have a form, macro, etc. with a distributable serial driver you could send me that actually works? Craig -- http://www.piclist.com hint: To leave the PICList .....piclist-unsubscribe-requestKILLspam.....mitvma.mit.edu>

have you tried using OLE? I am not a programmer, but have inherited a system which is using Word as the source of a control document, and then the results of the test are written to a duplicate of the document. In this case all the information is in tables in the Word document, with one column being test instructions, and the results get written into a second column, with another column having a date/time stamp added. I'm using VB3 and Word6 as that is what I inherited, but I believe Borland products had the OLE capability, possibly under another name. It is not exactly a whizz-bang process, but it does work for us. Failing that is it possible to do ODBC or SQL functions on Access? This may give you another way in, that is probably more generic. Using SQL would mean it should be readily portable to another database engine, or make your program potentially portable to other systems. Just a thought. -- http://www.piclist.com hint: To leave the PICList EraseMEpiclist-unsubscribe-requestspam_OUTTakeThisOuTmitvma.mit.edu>

> -----Original Message----- > From: Craig Lee [SMTP:picmespam_OUTENLIGHT.CA] > Sent: Wednesday, August 09, 2000 4:21 PM > To: @spam@PICLISTKILLspamMITVMA.MIT.EDU > Subject: Re: [PIC]:[EE]: Using Microsoft Access with RS232 > > Pekka, > > To much sunlight this time of year? > > Access 2000 is the intended target. It is still not clear how you do the > serial access. What is ADO2.5? > > I tried using MSCOMM32.OCX, I was surprised it was already installed in > my system directory. However, each time I go to use it, it says it is > improperly registered, or I don't have a license to use it. Screwey! > Unless you have a MS development tool that came with the COMM control, you won't have the necessary license to use the control at design time. An compiled application could however still use the control. I believe the MSCOMM control comes with the Professional or Enterprise editions of Visual Basic/ C etc. Regards Mike -- http://www.piclist.com hint: To leave the PICList KILLspampiclist-unsubscribe-requestKILLspammitvma.mit.edu>