EEVblog® Electronics Community Forum
Electronics => Projects, Designs, and Technical Stuff => Topic started by: tedre191 on July 17, 2013, 12:10:15 am
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Hi,
I just receive my pcb from OshPark for my new project and i can't get the ft232rl chip working.
When I plug my board to my computer, drivers are installing and I can see the TX led light up when i'm sending data with Putty.
On a loopback test, RX and TX led light up but I receive only 0x00 values back.
Am I missing something ?
Thanks
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Unless I am mistaken, it generally helps to connect the RX/TX pins on the FTDI to the MCU... (Or maybe the net names are invisible in Eagle?)
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Sorry, my mistake. Indeed, RX and TX are connected to the MCU TX and RX, names are not visible in that screenshot.
To do my loopback test, I removed the MCU and connected pin 1 and 5 together. I tried with and without the two 1k resistors.
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I tried with and without the two 1k resistors.
I was about to suggest that...
CTS might want to be pulled up?
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Download "FT_prog" from the FTDI website, have a look at how things are configured (the FT232R has onboard EEPROM).
It should be trivial to join TX & RX and use something like Hyperterminal to loopback - you may have flow control setup??
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CTS might want to be pulled up?
I just tried, didn't work.
Download "FT_prog" from the FTDI website, have a look at how things are configured (the FT232R has onboard EEPROM).
It should be trivial to join TX & RX and use something like Hyperterminal to loopback - you may have flow control setup??
Flow control is set to "None". I downloaded FT_prog and i'm able to read the FT232R EEPROM content.
None of the options in "Hardware Specific" are enabeled.
I'm probably missing something .. :(
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Did you buy the chip from a known source or eBay / AliExpress? There are dodgy fakes doing the rounds if I recall correctly.
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Did you buy the chip from a known source or eBay / AliExpress? There are dodgy fakes doing the rounds if I recall correctly.
I bought the chip on eBay (2 of them, both the same issue).
http://www.ebay.ca/itm/140838941057 (http://www.ebay.ca/itm/140838941057)
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You got fake chips.
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You got fake chips.
yep very likely, I bought a board from Itead , same issue. They admitted they had been caught with fakes. They replaced it. The QC sticker must have been for the board only I guess
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RTS and CTS are active LOW, either pull them down, or link RTS to CTS so it's signalling itself. Don't know if it will help, but worth a try huh.
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No need to do anything with the control lines. Hooking up tx and rx is all you need for a basic connection.
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You got fake chips.
Or just defective...
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Thanks everybody, I'm gonna buy new chips (from Digikey this time) and give them a try.
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Just received my new chips from Newark and everything is working now. Thank you all for your help ! :D