Society of Robots - Robot Forum

Electronics => Electronics => Topic started by: Admin on March 03, 2008, 10:25:04 PM

Title: RFID Transceiver, where is Rx and Tx?!
Post by: Admin on March 03, 2008, 10:25:04 PM
For a project I am working on, I am required to use this RFID device:
http://www.nordicsemi.com/index.cfm?obj=product&act=display&pro=64
nRF2401A Transceiver

Looking at the pinout, I can't figure out what is Tx and Rx.

I guess pin 3, Data Out 2, is Tx.

But where is Rx? And what does pin 7, Data Input Output, do?

I realize I haven't carefully read through the datasheet yet, but I have one week to build an entire custom robot arm (plus my normal 40 hour work week) and my brain is frying here . . .

Hope someone can help asap!
Title: Re: RFID Transceiver, where is Rx and Tx?!
Post by: frank26080115 on March 03, 2008, 10:58:15 PM
That's not an RFID transceiver, I have two nRF24L01s from SparkFun, they are just really easy to use and reliable radios

Unless you want to use them as RFIDs...

Anyways, read page 16 and down for configuration info and timing diagrams, the most useful parts.
Title: Re: RFID Transceiver, where is Rx and Tx?!
Post by: izua on March 04, 2008, 06:08:01 AM
you can try CC1000 or the rfxxxx chips from nordIC for a transceiver (both are smd)
Title: Re: RFID Transceiver, where is Rx and Tx?!
Post by: Admin on March 04, 2008, 09:36:52 AM
Oops, I saw RFDi and somehow thought I saw RFID.

I am actually using the RFD21006, which supposedly has a nRF2401 Module in it. No idea what else it has, since I can't find a datasheet, just a pinout.

(I'd link you to it, but the www.rfdigital.com site won't allow a link to other than the main page . . .)

I'm still confused on where to connect Tx and Rx . . . I only see one DATA pin . . .

On page 9 on the datasheet (http://www.nordicsemi.com/files/Product/data_sheet/nRF2401rev1_1.pdf) I found this:
Mode               PWR_UP   CE   CS
Active (RX/TX)       1         1     0


My assumption is that I attach my mcu digital output lines to those three pins to control the transmission mode, plus ground and power. But . . . what about my Tx/Rx pins from my mcu, where do they go?

I'm also assuming I can ignore the CLK pins, right?
Title: Re: RFID Transceiver, where is Rx and Tx?!
Post by: frank26080115 on March 04, 2008, 10:04:32 AM
I really think it's synchronous, so you have to use SPI on your microcontroller and emulate another SPI interface with software, or use your USART in synchronous mode.
Title: Re: RFID Transceiver, where is Rx and Tx?!
Post by: Admin on March 04, 2008, 12:48:50 PM
Quote
I really think it's synchronous, so you have to use SPI on your microcontroller and emulate another SPI interface with software, or use your USART in synchronous mode.
hmmmm complicated . . . by complicated I mean I'd have to figure out how to use SPI :P


Anyway, scratch this whole thread. My client recently decided this isn't the right technology for what he wants, so I'm not pursuing it any further.