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10 years, 10 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, 10 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, 10 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