Reading DS2406 And DS2423 using TMEX and VB6

by **maeron** » Tue Feb 19, 2008 12:59 pm

Hi all,

Im writing a litte class lab for students to program 1 Wire devices from Visual Basic 6. We use TMEX API.

I have some problems with the DS2406. What should I send for setting the switch value? flag = TMAccess(SHandle., ??)

The same code I use for DS2405 does not work on DS2406.

I havn't started on the DS2423 counter yet but I can't find anything (examples or so) on how to acces this device from Visual basic 6.

Any other examples for use with 1 wire devices and Visual Basic 6 and TMEX is very, very, very welcome

Best Regards
Maeron

by **Digit** » Tue Feb 19, 2008 1:14 pm

Did you try the Software Search Engine?
http://www.maxim-ic.com/products/ibutton/example/
DS2406 + ALL + TMEX + VB gives a result...

For DS2423 i can provide Delphi source, so you can translate that.
But first try the above search on that one to.

by **maeron** » Tue Feb 19, 2008 1:23 pm

Yes I've seen that but that code does not set the switch it just check for it and try to acces its filesystem that generates a error.

by **Digit** » Tue Feb 19, 2008 1:28 pm

In that case:
Forum member mhwlng wrote a 1-wire plugin for Girder:
http://www.promixis.com/forums/showthread.php?t=12458
He knows[:)]

by **maeron** » Tue Feb 19, 2008 1:38 pm

Thanx

I will contact him

/M

by **Mhwlng** » Tue Feb 19, 2008 2:07 pm

c++ source code is included in above mentioned plugin...

see switch.cpp

I used code from here as an example :

http://sheepdogsoftware.co.uk

Marcel

by **maeron** » Tue Feb 19, 2008 2:41 pm

That was fast *smile*

Thanx alot I will check that page ...

And thax again
/Maeron

by **maeron** » Tue Feb 19, 2008 4:00 pm

mhwlng,

I found what I was looking for in you C++ code, thanx for sharing.

I will try this tonight and see if I can get it to work

/Maeron

by **maeron** » Tue Feb 19, 2008 7:05 pm

Hmm I tried to send the following command "flag = TMTouchByte(SHandle, &H1F)" HEX 1F = 31 thay SHOULD set channel a AND B to ON but it does not work

the complete code I tried:

Code: Select all: '// Write STATUS command flag = TMTouchByte(SHandle, &H55) CRCByte = &H55 CRC16 = TMCRC(1, CRCByte, CRC16, 1) flag = TMTouchByte(SHandle, &H7) CRCByte = &H7 CRC16 = TMCRC(1, CRCByte, CRC16, 1) flag = TMTouchByte(SHandle, &H0) CRCByte = &H0 CRC16 = TMCRC(1, CRCByte, CRC16, 1) ' 31 00011111 A on B on = 001F HEX ' 127 01111111 A off B off = 007F HEX ' 63 00111111 A off B on = 003F HEX ' 95 01011111 A on B off = 005F HEX '// Skicka koder om Av Och P flag = TMTouchByte(SHandle, &H1F) CRCByte = &H1F CRC16 = TMCRC(1, CRCByte, CRC16, 1)

What am I doing wrong?

/Maeron

by **Mhwlng** » Tue Feb 19, 2008 7:36 pm

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">What am I doing wrong?
/Maeron
<hr height="1" noshade id="quote"></font id="quote"></blockquote id="quote">

Sorry, but at the moment, I don't have time to study the 1-wire specifications again and it's too long ago for me to remember exactly how the 1-wire protocol works, from memory...

is it wired correctly ?

your vb example only shows a subset of the complete tmex code (see onewire.cpp, tmex.cpp)

if you perform a device list( see list.cpp) do you see it ?

I know the C++ code works, because I tested it myself with all supported devices. (I used a 6-PIN TSOC 2406 with a led and resistor going from pin 3 to +5V on a breadboard)
I don't remember, if I needed to set output A to 0 or 1 to make the led light up...

by **Digit** » Tue Feb 19, 2008 9:53 pm

And i've never done anything with a DS2406...[:I]
So only thing i could do is help you search for possible mistakes in translating to VB. Send me PM if you think that is helpful.

by **maeron** » Tue Feb 19, 2008 11:07 pm

The device is found by the program and it shows up correctly.

Here is the complete function:

Code: Select all: Function SetFlipFlop(S As Integer, RoMID As String, Fam As Integer) As Boolean '// Start session SHandle = -1 Num = 0 While (SHandle <= 0) SHandle = TMExtendedStartSession(PortNum, PortType, vbNullString) Num = Num + 1 If Num > 50 Then Exit Function ' This is just to break the function if we cant communicate with the 1 wire bus Wend 'Soo now we have handle on the 1 Wire bus 'Now we are going to lookup the DS2406 we wanna change ' We are looking for the RomID If TMFamilySearchSetup(SHandle, state_buffer(0), &H12) = 1 Then While TMNext(SHandle, state_buffer(0)) = 1 '// Read the ROM number ROM(0) = 0 flag = TMRom(SHandle, state_buffer(0), ROM(0)) '// Check for the correct type If ((Fam And &H7F) = (ROM(0) And &H7F)) Then '// Create a string out of the ROM number romstr = "" For i = 7 To 0 Step -1 If (ROM(i) <= &HF) Then romstr = romstr + "0" romstr = romstr + Hex$(ROM(i)) Next i If romstr = RoMID Then '// Write STATUS command flag = TMTouchByte(SHandle, &H55) CRCByte = &H55 CRC16 = TMCRC(1, CRCByte, CRC16, 1) flag = TMTouchByte(SHandle, &H7) CRCByte = &H7 CRC16 = TMCRC(1, CRCByte, CRC16, 1) flag = TMTouchByte(SHandle, &H0) CRCByte = &H0 CRC16 = TMCRC(1, CRCByte, CRC16, 1) ' 31 00011111 A on B on = 001F HEX ' 127 01111111 A off B off = 007F HEX ' 63 00111111 A off B on = 003F HEX ' 95 01011111 A on B off = 005F HEX '// Send the HARDCODED 00011111 to the Switch flag = TMTouchByte(SHandle, &H1F) CRCByte = &H1F CRC16 = TMCRC(1, CRCByte, CRC16, 1) End If End If Wend

by **Mhwlng** » Tue Feb 19, 2008 11:46 pm

I just tested the plugin in girder with a 6-PIN TSOC 2406 with a led and resistor going from pin 3 to +5V on a breadboard)

and I can confirm :

127 -> led off
31 -> led on

note that you need to apply 5V!
it doesn't work on parasitic power...

(on parasitic power, it still shows up in the device list, though)

Marcel

by **maeron** » Wed Feb 20, 2008 7:55 am

Doesn't it work if powered with the DS94940R (The USB)?
What I understood IT could power the 1 wire network.

/Maeron

by **Mhwlng** » Wed Feb 20, 2008 10:24 am

only simple devices like DS18S20 temperature sensor work on parasitic power.

other devices can be detected on parasitic power, but the rest of the functionality requires 5V to work reliably...

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