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cagdask
- 1st March 2007, 23:40
Hi all, i am a newbie designer from Turkiye. I want to connect 16f628 with ftdi232bm. actually designed and assembled an evolution board without eeprom. windows notices new device but notify me as device is not recognized, trying to install driver does not work neither. i thought maybe problem is because of not connected eeprom pins.(otherwise its possibly my awfull assembly). i am really in mass here. i observe correct voltage levels on pins. but nope its not working!!!

any help will be really appreciated...

skimask
- 2nd March 2007, 00:01
Hi all, i am a newbie designer from Turkiye. I want to connect 16f628 with ftdi232bm. actually designed and assembled an evolution board without eeprom. windows notices new device but notify me as device is not recognized, trying to install driver does not work neither. i thought maybe problem is because of not connected eeprom pins.(otherwise its possibly my awfull assembly). i am really in mass here. i observe correct voltage levels on pins. but nope its not working!!!

any help will be really appreciated...

You can't enumerate an FTDI232BM without a custom descriptor. 232BM datasheet says the custom descriptor is in the external eprom. You don't have an external eprom. Therefore, you can't enumerate an FTDI232BM without an external eprom.
However...the datasheet also states that the -232BM without an eeprom, when enumerated, will send back an FTDI VID&PID and power descriptor. So, make sure your driver's VID & PID match the generic FTDI VID & PID (i.e. you didn't change them).

cagdask
- 2nd March 2007, 00:12
skimask : thank you for your reply. but i've dont changed about driver. in fact it never comes to that point. i mean it never asks for drivers at all. i got an error msg : "USB Device not Recognized. One of the USB devices attached to this computer has malfunctioned, and Windows does not recognize it."

wfvisser
- 11th April 2007, 15:47
Hi, I had a similar problem, although I was trying to connect a FT8U232AM(not BM), to a PIC16F628A, and a mac rather than windows. The symptoms were similar though: it recognized that the device connected, but couldn't connect to it or use the virtual serial port. It turns out that you do need to add a pullup or pulldown resistor to one of the pins of the FTDI chips that normally connects to the EEPROM. I don't know the details by heart, but it is described in the datasheet or one of the application notes. You may have to look for it in the documents, because I do remember that it wasn't described in all of the documents and I missed it the first time. It may well be similar for the BM chip you are using. Hope this helps. PS, let me know if you can't find it. I'll check out the circuit I made and tell you what I did to solve it.

phoenix_1
- 19th May 2007, 20:37
Hi to all.
I need FT232BM omly one sample buth i can't get in in Serbia !
Do somebady want to send me one sample PLEASE.
For contact information [email protected]

If I can help to anybody of you I will help.
I have many thing interesting for PICMICRO MCU !!!!

Best regards phoenix_1

skimask
- 19th May 2007, 21:23
Hi to all. I need FT232BM omly one sample buth i can't get in in Serbia ! Do somebady want to send me one sample PLEASE. For contact information [email protected]
If I can help to anybody of you I will help. I have many thing interesting for PICMICRO MCU !!!! Best regards phoenix_1

http://apple.clickandbuild.com/cnb/shop/ftdichip?op=catalogue-products-null&prodCategoryID=6&title=FT232BM

phoenix_1
- 20th May 2007, 09:27
thanks for link buth from serbia i can;t pay by paypal or any service internet
pay sistem.That is reasen to I ask to someone send me one sample via clasic mail.

If you can order me one and send me by clasic mail package please.

best regards phoenix_1