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Trying to figure out serial lcd from sparkfun electronics on a picaxe board - 28 pin

Hello there, haven't asked too much on here lately but I was wondering if anyone could help me out on programming Serial LCD from sparkfun - http://www.robotshop.com/productinfo.aspx?pc=RB-Spa-330&lang=en-US- also found here- http://www.sparkfun.com/products/9393. This is for my 4th step or advancement on my start here robot. I have added a SRF05, LDR, and this LCD which is the last thing that I have yet to figure out so almost there I suppose : ) . I have been reading Chris's old post on this product (http://letsmakerobots.com/node/4114). I have tried setting frequencies, baud rates, etc. The pin I am using I believe is 0 and I think I have everything set up right. Im using the output pins and everything so unless I have it hooked up wrong I don't know what else could be wrong besides the programing. Bought the thing because I liked the simple three pin hookup- ground, 5V, and signal. If anything my signal could be hooked up wrong pherhaps, I am wondering if the black and yellow wires should be switched-ground and yellow, because I thought ground was on the edge of the output board.... anyhow I can send pics if anyone wants (will try to make the clearest ones as possible). 

Here is my hookup to the lcd. (yellow on end, red in middle, and black on the inside of output pins- I thought the black and yellow should be switched but anyhow i get confused easily sometimes when things don't work haha)

LCD wires on board

My LCD wires MUST and should be correct, yellow in on RX or signal, Red on the V, and the Black on the ground. 

Here are a few programs I was going to start with-


setfreq m8




serout 0,T9600_8,("hello")


goto main





setfreq m8


serout 0,T9600_8,("hello")


wait 10



Again this is after I have read others posts so I hope I have some of it close atleast (hope I'm gaining haha). Any programs you know will work or other things of information you think will help please send them this way :) Thanks 

P.S. - datasheets on this thing and schematics are on the websites. Thanks and have a nice day




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  • Get the setfreq out of the main loop
  • The setFreq command (in this case) doubles your clock frequency, thus everything is going to work twice as fast. I.e. 4800 baud = 9600 baud and pause 2000 = 1 second (I assume this, you did not mention what chip you are using --other than being a 28 pin)
  • You are resending the "hello" (in the first example) as fast as the main loop can loop (this is not good). You should only need to send it once
  • I can't remember if you need T4800 or N4800


I think that's it.

OK thanks Chris, Im using the let me see what is it L293D and PICAXE-28X1 IC (same chips as the start here robot). Will this program work otherwise to atleast get something up there or not? If not is there any code/program you could lend me to get me goin? Thanks again. 

Well, you are all set then. It has been a while since I played with this stuff and picaxe chips but all in all, you will use one of these:





Beyond that, you have the command down, just be sure not to keep sending it over and over. That's it!


Thanks again. Hopefully it will work haha :)

Do I need to set up the screen first or anything Chris? I fail to see what is wrong. I tried your commands and used the same code... so I dont know. Heres what I have now. -

setfreq m8


serout 0,T4800_8,("hello")

wait 10


How is that what next I guess haha hopefully I can get this to alteast turn on... :(

Its the contrast, dude. Adjust your contrast with the little pot on the back.

sorry man  but I could adjust that screw all day long.... and i doubt itd do anything..lifechangeing. I made it tight and loose and still nothin.. absolutely nothin. I dont know if you have a program still saved somewhere or what you want to do now. I will send you any pics, info whatever... Im stuck sadly. Sorry to bother you so much, hope this isnt pissing you off too bad haha. 

Could it be fried or not functional by any means? Should I send it back and ask for another one?

I am stuck, my man. Or at least I have given you all I know to do. Couldn't hurt to give SparkFun an email.

I will keep messin and maybe buy another one and see if that one works for some reason. Get new wires and so on see if that does anything. Ill take your advice and email Sparkfun too.  If nothing happens well i guess ill send it back. thanks for all your help Chris.