Serrxd

[marky26uk]

Hi all, i'm having maor problems with the serrxd now on the 28x1, i really feel like throwing these 28x1's in the bin.
What i'm doing is sending a string "READY" out from my QBASIC program & trying to receive on the picaxe via SERRXD ("READY").
Looks like it's a timing issue again & no matter what i set calibfreq to it just won't work.
Any ideas anybody or technical please

Mark

 

[leftyretro]

Hi all, i'm having maor problems with the serrxd now on the 28x1, i really feel like throwing these 28x1's in the bin.
What i'm doing is sending a string "READY" out from my QBASIC program & trying to receive on the picaxe via SERRXD ("READY").
Looks like it's a timing issue again & no matter what i set calibfreq to it just won't work.
Any ideas anybody or technical please

Mark

Well keep an open mind. The fact that the pixaxe can communicate with the editor program via downloading may point to other possible cause for your PC program symptom.

Troubleshooting (hardware or code) is an art that requires an open mind, Looking for facts or hunches, implementing test programs to prove or disprove a assumption. Good luck and I'm sure you will get other help here.

Lefty

 

[SD2100]

Post your QBASIC program so we can eyeball it. Can't be too much wrong ??.

 

[moxhamj]

There are many other possibilities besides timing. Do you have an 08M or similar simpler picaxe to test it with?

 

[demonicpicaxeguy]

the problem is that the serial input on the picaxe (unless you use the hardware serial port) is not buffered meaning that unless the picaxe can process each incomming byte quickly enough to be ready for the next

instead of sending "ready" send the individul bytes
send "r" then wait 500us then send "e" and so on until all the bytes are sent

that way the picaxe is given time to process each byte and be ready for the next to be recieved

 

[BrendanP]

I have had similar problems recieving serial data from a GSM module. I have found the hardware serin to the scratch pad the way to go.

 

[Technical]

There are no known issues with serrxd timing issues from a PC - as already stated the chip downloads via the same internal serrxd serial routines so no timing adjustments should be necessary- mabe you should post your whole program and the gbasic code.

Also make sure you are using Programming Editor 5.1.5 or later.

 

[SD2100]

This works....

#Picaxe 28x1
do
    serrxd("READY")
    high 0
loop

Send one character at a time with a small delay.

OPEN "COM1:4800,N,8,1,TB0,RB0,RS,OP,CD0,DS0" FOR RANDOM AS #1
    PicaxeData$ = "READY"
    FOR Loop1 = 1 TO LEN(PicaxeData$)
        PRINT #1, MID$(PicaxeData$, Loop1, 1);
        slow = TIMER + .01
        WHILE TIMER < slow: WEND
    NEXT
CLOSE #1

 

[TERD]

In my experience it's a commom occurance on the x1, but not a problem.
Check your hardware connections, make sure baudrate at the term is 4800, then do this:

main:
serrxd b0
sertxd b0
goto main

send '1' frm the serial terminal and see what comes out. Every x1 that i have used (without calibration) has returned a 'q' or an 's' when a '1' was sent.

Then try messing with calibfreq again, using negitive numbers and see what comes out then.

It will work.