Serial comms / Bootloader

[koossa]

-did you disable the handshaking?
<font color="red">Yes</font>
- What about if you use MicroCode Studio Serial Communicator instead?
<font color="red">MicroCode Studio Serial Communicator works!!!</font>
<font color="red">But with visual basic or hyperterminal it does not work?
Any idea what is the difference between the 2?
</font>
-Is your MCLR pin is tied to VCC via resistor?
<font color="red">Yes</font>

[mister_e]

In VB you'll need to disable the DTR line. Here's a usual COM port setting in VB

    '   Serial Communication Definition
    '   ===============================
        '
        With MSComm1
            .CommPort = 1                 ' Using COM1
            .Settings = "9600,N,8,1"      ' 9600 bauds, no parity, 8 data bit,
                                          ' 1 stop bit
                                          '
            .Handshaking = comNone        ' no handshaking
            .DTREnable = False            ' disable DTR line.. avoid PIC stuck if using
                                          ' bootloader circuitry
                                          '
            .EOFEnable = False            ' disable EOF event
            .InputMode = comInputModeText ' Get Text from COM port
            .RThreshold = 1               ' amount of character to be receive prior to
                                          ' generate a CommEvent
                                          '
            .InputLen = 0                 ' get the whole string
            .PortOpen = True              ' open COM port
            End With

MCS don't use and disable the DTR line for you.. not Hyperterm (wich i stay far of)

[Acetronics2]

Hi, Steve

Have a look there : http://www.beyond-designs.com/PC_ports.htm#VBHexTerm

or :

http://www.synthmodules.com/other/VBHexTerm-Setup.exe

... nice !!!

Alain

[Melanie]

Steve - Before you confuse half the forum readers - that's not a MAX232 jpg...

[mister_e]

Yes it is! comming directly from the Maxim datasheet bellow...
http://pdfserv.maxim-ic.com/en/ds/MAX220-MAX249.pdf
there's some little character to read at the bottom of the picture ;-)

From the Maxim datasheet:

<img src="http://www.picbasic.co.uk/forum/attachment.php?attachmentid=576&stc=1&d=1130688459 ">
<img src="http://www.picbasic.co.uk/forum/attachment.php?attachmentid=577&stc=1&d=1130688459 ">


From the Texas Instruments datasheet:

<img src="http://www.picbasic.co.uk/forum/attachment.php?attachmentid=578&stc=1&d=1130688459 ">

[Melanie]

The correct pic is in the datasheet you just posted, but what I'm trying to say is that the jpg you've put up a couple of posts above is not of a MAX232... a MAX232 does not have enable connections on it's inverters. I refer you to Figure 5 on Page 17.

[koossa]

COOL!!

DTREnable is working!!!!
Thank you Steve!!!