Q2686 with two external RS232 peripheral


#1

Hello,
I’m develop hw with Q2686 with GPS module linked via UART2, and I would link bluthoot chip(with RS232) via UART3(Q2686 USB), because is necessary use UART1 on Q2686 for debug with OpenAT. Is present a electric schematic to link bluthoot chip via USB to Q2686 ?, is possibile use a FTDI chip to interface bluthoot with Q2686 via USB port ?

Thanks


#2

No, it’s not posible, because the USB port is a Device port - you would need a Host port to do this!

Anyhow, you can use UART1 for both your application and for debug - see: viewtopic.php?f=53&t=2509&p=11123&hilit=external+com#p11123


#3

Bluetooth modules are also available with SPI…


#4

Hiya,

Maxim also ships SPI Uarts…check out Maxim IC.

ciao, Dave


#5

the Bluthoot module with SPI is diffucult to find, instead the MAXIC 3100 is a product to interface Bluthoot chip with RS232 and Q2686 with SPI communication.
Should I try the solution with MAXIM IC and I shall know. Thank you


#6

Are you referring to the FTDI Vinculum VNC1L? In that case it´s possible, the Vinculum is a USB HOST, not like the FTDI FT232BM (for example) as Awneil said. But the VNC1L it´s ready by default for reading USB Mass Storage Devices, if you want to use it as a “clean USB-UART converter” you have to set it up… nothing easy. I think an easier solution is to implement your Bluetooth device on SPI with a Maxim IC, as Dave said.


#7

Hiya,

The VNC1 uses a pretty strange SPI format - it’s not really SPI as we know it. I interfaced one to a PIC micro earlier this year, and ended up having to bit-bang the SPI interface as I couldn’t get the VNC1 to talk to the hardware SPI master in the PIC.

The Q26xx doesn’t give you fine enough timing control to bit-bang a SPI interface at any reasonable speed…

All that said, if you do get the VNC1 interfaced to the Q26 via SPI, I’d be interested in knowing how you did it!

ciao, Dave