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dexterprashant
01-03-2010, 04:54 PM
hi
can u solve my doubt..
In case i have to give digital inputs to RF remote not by switches but by the anlog signals converted into digital by ADC... So is it possible to have an ADC on remote for RF communication? or is there a better solution for this?

vikas
01-03-2010, 06:06 PM
Doing this will work but not reliably and will give very low speeds.
Use a proper RX/TX IC .

allbits
01-03-2010, 09:09 PM
Is it that you already have an RF remote, and you want to add some kind of control to it, rather thatn the one which it already have??

Can you explain your requirement better?

dexterprashant
01-04-2010, 12:36 AM
i have to make an RF remote control with proper RX/TX module which will be ASK based.. the transmitter IC (HT-12E) instead of getting input from the push buttons will get input from ADC and ADC will be having analog input from vltge sources (like sine voltages,etc.).. so its just that instead of giving a direct digital input i will be providing it thru ADC.. also i will be using AT89S52 microcntrlr at receiver side..
this is detailed explantn..
plz tell me is this feasible or is there a better alternative ??

vikas
01-04-2010, 01:28 AM
Looks fine to me , You can also use a ADC on the microcontroller and establish a serial link b/w the tx/rx at say 2400 bps with the values being sent over it.

dexterprashant
01-04-2010, 12:42 PM
but if i use an 8 channel adc and want to send its output thru HT-12E (tx) to rx then is it possible to use a mux after ADC and then give this single output of mux to HT-12E for transmitting.. as only on bit can be sent at a time..

docel
01-05-2010, 12:14 AM
Why all the hassles when something simple can be made in an easier manner??

1. The HT12E will latch if you try changing its Data input pins' state. You have to repeat the signal 3 times before it says 'ok' and change its o/p.
2. it is quite sensitive to RFI .The Micro controllers clock signals must be severely negated or it will latch the encoders o/p.

Why not generate the encoder pulse string directly from the Micro and modulate the ASK module?

dexterprashant
01-05-2010, 12:58 AM
Why all the hassles when something simple can be made in an easier manner??

1. The HT12E will latch if you try changing its Data input pins' state. You have to repeat the signal 3 times before it says 'ok' and change its o/p.
2. it is quite sensitive to RFI .The Micro controllers clock signals must be severely negated or it will latch the encoders o/p.

Why not generate the encoder pulse string directly from the Micro and modulate the ASK module?

hey docel thankx for that
but the problem is that i am going to apply an analog input voltage to 4-channel ADC and give its output which will be a 4-bit pattern to HT-12E which have 4 data input pins.. and now this can transferred to receiver on which further processing will done using mC..
is this possible ?

docel
01-16-2010, 01:16 AM
ok....but make sure that the bit conversion is slow, and the Vcc of the encoder is atleast 6V, otherwise the HT12E will latch up.