Newbie radio link issue

[George]

Have found the problem, wrote to the manufacturer and they replied with this:

The ER modules are pre-set to 19200 baud. If you cannot talk to them at this speed then you cannot use them. One of the best ways to get around this is to purchase the eval kit for 55 pounds. This has two pcb boards, leads, antennas etc. which enable you to connect the module to a PC that can communicate at 19200 baud. Then you can send the ER command to change the board rate to PIC baud rate you need for example 2400 etc.

So I was thinking about building another board with a 20MHz crystal and try send it the commands to change down to 2400. If I do this - am not really sure of the syntax - it says in the datasheet the comm settings is ER_CMD#U1 so do I send it like this SEROUT pin,baud,["ER_CMD#U1"] ???

Thanks again for all your guys input so far

[mister_e]

O.K. i heard you but any link to the datasheet?

[George]

Sorry - here it is: http://www.lprs.co.uk/pdf_directory/....3-sept-05.pdf
BTW - if I make a 20MHz board - what size caps do I use with my crystal? I use to use 22pF with 4MHz - does that mean I use 5pF with 20MHz?
cheers

[mister_e]

the recommended cap are listed in your datasheet. usually 22pF is a nice choice.

In theory your SEROUT is good. BUT, to me, you still have to transmit it with the default baudrate.. so it doesn't solve the problem unless you buy the suggested module to reprogram them first.. waste of time and money to me.

BTW @19200 baud, for ANY reliable serial comm, i'll suggest you to use the PIC USART with HSERIN/HSEROUT instead.

[George]

You don't think SEROUT2 running 20MHz could send enough data to change the default setting in the radio module? Is my syntax correct in how I'd send it? If you think that the serout won't do 19200 then I think I'll just cut my losses and try find another module that just works, the manufacturer did say that I could send it back and they would change it in the factory and send it back to me - however they r on the opposite side of the planet!

[mister_e]

Try with DEBUG first. it's probably better. BUT both of them worth a try for sure.

[George]

sweet - will try with debug - is my syntax correct?

SEROUT pin,baud,["ER_CMD#U1"]

sorry - i mean:

DEBUG "ER_CMD#U1"

???
Thanks

[skimask]

You don't think SEROUT2 running 20MHz could send enough data to change the default setting in the radio module? Is my syntax correct in how I'd send it? If you think that the serout won't do 19200 then I think I'll just cut my losses and try find another module that just works, the manufacturer did say that I could send it back and they would change it in the factory and send it back to me - however they r on the opposite side of the planet!

If you've got a few extra crystals handy (and assume that you just happen to have the right values ), how about tell the compiler you're using 2400 baud with 4mhz, but actually use a 32mhz. The compiler won't know the difference and you'll be running at 19,200.
But since you're running a 16F series, you're probably limited to 20mhz (depending), so maybe, tell the compiler you're running 4mhz with 9600 baud, and actually use 8mhz, to which you'll get 19,200 baud...
But there I go thinking again...gotta stop that...

[mister_e]

yes, tricking the way you said should work... but i don't see any advantage here.