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10 years, 9 months ago.
UART
Hi guys, I am tottally new to this, just got my freedom Board FRDM KL25Z. I am also using an Arduino wireless photo shield attached to the FRDM board, to connect my xbee.I ve got a problem to understand the UARTs that the FRDM provides.and the use of them.could you give me a hand?
2 Answers
10 years, 9 months ago.
/media/uploads/philthegr/frdm-kl25z_schematic.pdf Hi, i ve uploaded the FRDM KL25Z schematic as well.There are 3 UARTS in the FRDM KL25Z board. One is for debug,one is for the xbee, one is for a display interface?is that right?Could you give me an idea about the UART pins connection?
That all depends on the shields connections. UART pin connections are shown on the handbook page: http://mbed.org/handbook/mbed-FRDM-KL25Z
posted by 22 Jul 2013Thanx Eric, i ve seen that already.However i m struggling to deal with the shield i am using http://arduino.cc/en/Main/ArduinoWirelessProtoShield
posted by 22 Jul 2013I assume that shield uses the 'normal' Arduino pins for serial connection, PTA1-PTA2. Sadly the KL25Z uses those also for serial communication via the SDA port, see for a discussion and solution: http://mbed.org/questions/1365/Using-UART0-on-FRDM-KL25Z-through-J1-hea/
posted by 22 Jul 2013
10 years, 9 months ago.
You may have the problem with voltage levels of the TX and RX lines. The freedom board's pins aren't designed to be 5V tolerant, and there is a level changer on the Arduino wireless shield. You may want to watch out for this.
It is handy if you specify more precise what the issue is.
posted by Erik - 22 Jul 2013