Windows CE 802.11b VFP 6 -- no wheels? 3

[alan232]

Hi Everybody,

As both a question and an update on my quest, I'm posting this where I left off...Please direct me elsewhere if needed. (I am running out of time!)

As was in my previous questions (if there still in the forum), I have a very limited time to provide a front-end form on a handheld pc to my existing foxpro database. After much internet searching, I purchased an HP IPAQ 4705 based on its excellent full VGA display, memory, and battery life. (It was somewhat pricey but I feel well worth it). It uses Microsoft's newest version of Windows CE (windows mobile os, second edition). After much more extensive internet research, I decided initially on Visual CE ( by Syware) as a quick method of creating a frontend to the VFP server. My basic scheme was going to be Visual CE on the HP IPAQ <-->mEnable<-->VFP on desktop. I created a common file for both mEnable and VFP to 'sync' with. (mEnable is Syware's software to enable record sync via ODBC). On paper, it sounded perfect. Syware readily provided a trial version of visual ce. This was downloaded and as far as it would go, it did great--I was well on the way to finishing ahead of schedule. I have no intention of reinventing the wheel, so I purchased Syware's Visual CE-Enterprise editiong ($600) feeling pretty assured that it would work as advertised. Unfortuneatly, it did NOT work--it never would sync with the VFP table as the trial version did (and I have no idea if mEnable would have worked or not). I have since deleted it from my machine (and hope Syware will refund my money?).

After another week of internet research, I find I might have to invent the wheel for this combination HP IPAQ 4705 and Visual Foxpro 6 (on Windows XP)-- I can find no wheels out there!

Which brings me back to this forum. I am pretty good with code, from the old Assembler, Forth, Fortran, Basic, C, C++, Foxpro, etc.., but have no knowledge of how to start for WLAN (Wi-Fi) programming accross 802.11b using Windows CE as the client and Visual Foxpro as the ODBC server...

I sure need some suggestions towards the most direct path--I'm not looking to reinvent the wheel here, so If somebody knows of a working program for ANY or ALL of this, please let me know. Otherwise, can somebody suggest a minimal list of books or articles, etc., or software that I need to do this with? (i.e.,invent the wheel?)

Sincere and Desperate,
Alan

 

[DSummZZZ]

In your previous post as I recall, you never mentioned whether you were planning on live, synchronous updates or whether you were going to use batch updates.
If the handheld is going to be synchronizing data real-time using a constantly live connection, check into using TCP sockets via the Winsock control. Do some searches on Winsock and CE and you should come up with some examples most likely written in C++ or VB.
VFP can utilize the Winsock control also, so you could in all reality connect to a VFP socket and send a string (record) to a VFP server and it could add it to a table. You wouldn't need any sort of ODBC connection for that.

-Dave Summers-

Even more Fox stuff at:

http://www.davesummers.net/foxprolinks.htm

 

[alan232]

Hi,

Much thanks! My need is being driven by Blue Cross/Blue Shield of Tennessee that seems to think I have all day to write long treatise on patient problems. Hence, I am trully being forced to use real-time communication between myself and my receptionist such that data entered via the vfp server (receptionist) is transmitted via 802.11b to my handheld. It's not quite so important that my handheld immediately returns data to the server, as that could probably be done at the end of the day. (I guess it could be workable to manually enter the front office data into the handheld prior to seeing the patient, but I'm generally having to move quite fast and don't need the extra keystrokes of entering data that is already in the database).

Winsock's are entirely new to me. In simple terms, do they interface to the transmitter/reciever ...i.e., Wi-Fi of Windows CE and the server's ethernet ? (This area of programming has so many acronyms its easy to lose the concept).

Thanks again...now I have a starting point!
Alan

 

[wgcs]

Winsock is the basic interface to TCP/IP that Windows (95,98,ME,NT,2k,XP,CE/PocketPC) offers for applications to use.

Essentially, it's used something like this by a client:
Initialize Winsock
Open A Socket by Number on a Host Address (like, Open Socket 80 on Yahoo.com)
Read/Write from/to that socket handle.
Close the socket.

When you open the "socket" it becomes a stateful, reliable connection to the server its "connected" to (unless something catastrophic happens, like the server goes down, or the wifi router goes down (for a significant amount of time), or someone starts using a cordless phone that interferes with the wifi (for a significant amount of time). Brief interruptions are automatically overcome for you.

It is relatively easy to create a TCP/IP listener/server in VFP which could be running on your desktop, and your PocketPC/WiFi device could talk to VFP to get/send the needed data. The hardest part (to me) would be developing the UI program on the PocketPC (since I have little experience in that area).

An alternative, is to make your application web-based, and simply use a web browser on the PDA, and use your choice of active server: FOXISAPI, AFP, ASP+VFP COM, etc.

- Bill

Get the best answers to your questions -- See FAQ481-4875.

 

[Neil Toulouse]

Something we did that may not actually be useful to you as it requires PocketAccess which I believe has been dropped now?

But basically we had a requirement for part of our VFP system to be updated from a PDA, but it did not require direct/immediate updating of the main system so did not need a direct link.

For this purpose, data was exported from the VFP app to an Access database on the desktop (via ODBC), and then by using the DESKTOPTODEVICE function of the ADOFILTR.DLL installed with ActiveSync, this was then copied to the PDA. This copying process converted the Access MDB to a Pocket Access CDB.

Our PDA app was written by a 3rd party so can't help you there, but the data from the PDA was then converted to text files on the PDA which were then easily picked up and processed back into the main app as soon as the PDA was linked back to the desktop.

We had a few issues regarding backing up the data on the PDA (the PDAs we had lost everything if the battery went flat!!) but we got clever with storage cards, and came up with a nifty solution that even restored the PDA app with the data in this ever happened.

However, this was a couple of years ago and I guess everything PDA-wise has moved forward now so this post may now be irrelevant!

However, from experience if you link directly to you main data this would be the best solution. We were unable to do this because of the locations the PDAs were physically put in.

Neil

I like work. It fascinates me. I can sit and look at it for hours...

 

[alan232]

This maybe exactly what I'm going to have to do. It appears that Syware's Visual CE is better able to handle Microsofts' Access better then VFP. I may have to create an access table as a middle man between the handheld and the vfp server. Not exactly my first choice, but a definite possibilty. I wonder how hard it will be to write a form on the PDA (I've been spoiled with VFP!)...to quote the TV show, "The Truth is Out There".

Thanks for the great input!
Alan