Fez Cerbuino Bee - UART?

For the Xbee Module, there are 5 pins that are used : TX, RX, CTS, RTS and Reset. Do all these pins need to be used? Should I be keeping Reset Low for a Xbee device?

Wow, ok so it’s the device’s configuration!

The command to send is +++

By default the module is in Transparent Mode, which simply sends data to the configured target IP and port but does not respond with any data unless that remote host responds with data. To change it to API mode you send three plus symbols no CR or you can change it on the web interface to save the setting to NVRAM.

(See page 31 of the Zigbee WIFI module datasheet [url]http://ftp1.digi.com/support/documentation/90002180_G.pdf[/url]

Thanks for all the help everyone.

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@ Bill Gates, which fie are those #defines from?

@ Mr. John Smith - It’s in platform_selector.h which is in Solutions\FEZCerberus from the porting kit source


@ Bill,

#define STM32F4_UART_RXD_PINS {39, 3, 27} // C7, A3, B11
 #define STM32F4_UART_TXD_PINS {38, 2, 26} // C6, A2, B10
 #define STM32F4_UART_CTS_PINS {109, 0, 29} // G13, A0, B13
 #define STM32F4_UART_RTS_PINS {108, 1, 30} // G12, A1, B14

What pins do the CTS and RTS map to?

[Edit] Wait a sec, let me guess:

Com2 CTS = PA0, RTS = PA1?

So do the values
C7 = Port C pin 7 (aka PC7)
A0 = Port A pin 0 (aka PA0)
A1 = Port A pin 1 (aka PA1)

If so I guess I’m learning, if not; somebody please teach me.

Out of dispair, I ended up wiring up the Xbee Wifi Module to Socket 2 so that I can get access to the CTS and RTS for hardware flow control. Hardware flow control is my current objective.

Correct :slight_smile:

Okies, now for the big question:

Which handskake value do I have to use to enable CTS and RTS?

port.Handshake = Handshake.RequestToSend;


 port.Handshake = Handshake.XOnXOff;

[Edit] XOnXOff is software so it must be Request To Send? If so then does that also automatically raise the CTS pin when there is space in the buffer?