Newbie radio link issue

[George]

I'm new to serial comms and never tried a radio link before and am having troubles. I have an "easy radio" ER400TS and ER400RS chips, and am trying to link two PIC16F678 together with them. Have tried most things but gotten stuck - it does say in the datasheet for the easy radio chips that it defaults to 19200bps and gives the instruction to set data rate to 2400 as ER_CMD#U1

Many thanks to anyone who can give me some clue as to what I'm doing

Here's my receiver code:
@ DEVICE PIC16F676, INTRC_OSC_NOCLKOUT, MCLR_OFF, PROTECT_OFF, BOD_ON, CPD_OFF


'Define OSCCAL_1K 1
DEFINE OSC 4

TRISA = %001000
TRISC = %000000


ANSEL = 0 'disable analog
T1CON = %00000100
VRCON = 0 ' A/D Voltage reference disabled
CMCON = 7 'Disable comparitor

timesw var PortA.5
gosw var PortA.3
stopsw var PortA.4
timeset var byte
display var byte
time var word
b0 var byte
b1 var bit

clear
timeset = 1
PortA = 0
PortC = 0
serout PORTA.4,0,["ER_CMD#U1"] 'change receiver to 2400bps

Begin:

display = (1 << b0) - 1
PORTC = display
pause 100
if b0 < 7 then
b0 = b0 + 1
goto begin
Else
Pause 1000
b0 = 0
portC = b0
Endif

Start:

serin PORTA.0,0,["A"],timeset,b1 'Read receiver

disply:

display = (1 << timeset) - 1 'Set display to be bar type
PORTC = display 'output LEDs
goto Start


AND HERE'S MY TRANSMITTER CODE:

@ DEVICE PIC16F676, INTRC_OSC_NOCLKOUT, MCLR_OFF, PROTECT_OFF, BOD_ON, CPD_OFF

'DEFINE ADC_BITS 10
'DEFINE ADC_CLOCK 3
'DEFINE ADC_SAMPLEUS 50
'Define OSCCAL_1K 1
DEFINE OSC 4

TRISA = %111000
TRISC = %000000

'ADCON0 = %10000000
'ADCON1 = %000
ANSEL = 0 'disable analog
T1CON = %00000100
VRCON = 0 ' A/D Voltage reference disabled
CMCON = 7 'Disable comparitor

timesw var PortA.5
gosw var PortA.3
stopsw var PortA.4
timeset var byte
display var byte
time var word
b0 var byte
b1 var word

clear
timeset = 1
PortA = 0
PortC = 0

Begin:

display = (1 << b1) - 1
PORTC = display
pause 100
if b1 < 7 then
b1 = b1 + 1
goto Begin
Else
Pause 1000
b1 = 0
portC = b1
Endif

Start:

if timesw = 1 then settime 'jump to setime if triggered
if gosw = 1 then go
if stopsw = 1 then trnsstop
gosub disply
goto start

settime:

if timeset > 6 then timeset = 0 'if greater than max then reset
time = 0
pause 100
if timesw = 1 then settime 'wait till switch open
timeset = timeset + 1

goto start

disply:

display = (1 << timeset)' - 1
PORTC = display

return

go:

PORTC = 0
PORTC.5 = 1
pause 1000
for b0 = 0 to 5
toggle PORTC.5
SEROUT PortA.0,0,["A",timeset,1]
pause 100
next b0

goto start

trnsstop:

PORTC = 0
PORTC.0 = 1
Pause 1000
for b1 = 0 to 5
toggle PORTC.0
serout PortA.0,0,["A",timeset,0]
pause 50
next b1

goto start

[skimask]

I'm new to serial comms and never tried a radio link before and am having troubles. I have an "easy radio" ER400TS and ER400RS chips, and am trying to link two PIC16F678 together with them. Have tried most things but gotten stuck - it does say in the datasheet for the easy radio chips that it defaults to 19200bps and gives the instruction to set data rate to 2400 as ER_CMD#U1

Many thanks to anyone who can give me some clue as to what I'm doing

PBP manual, page 130 and page 137.
There's something on each of those pages that you've forgotten. Hopefully after you add that certain thing, all should be well. The rest of the code, at first glance, looks like it should be ok.

Another thing...make sure the whole thing works without the RF modules first, direct connect between the two PICs. That seems to be a common theme in most RF projects. People don't build up to the RF link, they just expect it to work on the first try (or the 100th ), and come to find out that the basic code was flawed in the first place.

[George]

PBP manual, page 130 and page 137.
There's something on each of those pages that you've forgotten. Hopefully after you add that certain thing, all should be well. The rest of the code, at first glance, looks like it should be ok.

I presume you are meaning the mode names? If so i used the code instead - ie. 0 = T2400

I'll try the direct connection now - I was thinking about it, but put it off

[skimask]

I presume you are meaning the mode names? If so i used the code instead - ie. 0 = T2400

I'll try the direct connection now - I was thinking about it, but put it off

I just looked at the PBP manual again. If you're using numbers, you don't need to include the file. My bad...
Also, the datasheet says to use inverted data, i.e. N2400 instead of T2400.
I'm just having a quick look at the datasheet now...so bear with me...

[George]

I pulled the radio modules off and did a direct connect - and it didn't work! All it was was making sure the internal oscillators were calibrated. Then it worked so my hopes were high for connecting the radio modules again - but alas, it was not to be. just doesn't work for some reason - I think it has something to do with the internal setup of the radio chips - for some reason (maybe their brand name) I thought it would be easy! And would just transmit data as it came into it's pin - but apparently u have to set baud into the receiver and there r a few other options which make it a bit complicated for a beginner.

[Ioannis]

If direct connection works and RF link does not (considering that the radios are communicating) then I would suggest to try sending only the bytes AAh repeatedly and see if the receiver gets the data.

If you have success then consider to use bi-phase or manchester encoding of the bytes to be transmited (forum has solution for this).

Ioannis