I would like to build a 4wd rover that will be remotely controlled using LabView on a pc. Eventually I would like to add an Xbee 900mhz link and hopefully video to the project as well. I am new to microcontrollers and have the Atom Pro 28 and their usb lab board. I have a basic understanding of electronics, I’m just lacking in the programming area.
How do I get a concatenated string of hex sent via serial to command HPWM and other outputs? The string is kinda long (PC80827F7F80FFFF000100320000X) the LabView code was originally written by another person for an underwater ROV. I am in the process of paring down the strings and removing a lot of unneeded items without wrecking the VI.
If someone could point me in the right direction, I would greatly appreciate it. If someone could just show me how to activate a simple output with Labview, it would be a step in the right direction
um since your question seems to revolve around how to program something in labview wouldn’t it make more sense to post this type of question on a labview support forum and tell them your application is controlling an rov than posting it on a robotics forum asking about how to write labview code?
perhaps an analogy would be walking into an alanon group session looking for help with a compulsive gambling problem… just a thought.
also maybe I misunderstood the point of the question… or which end of the system you were asking for help with. I’m not really sure.
Sorry, I think I drank too much coffee when I posted the question.
I understand the LabView end well enough to get it to send whatever string needed. As far as the Atom Pro goes…I’m clueless. If I set labview to send a hex string indicating a button pressed or joystick position (usually something like -100 to 100 decimal then converted to hex). How I get that hex value to to point to a command in atom code. I imagine would there would be a table or array of some sorts. I really don’t understand variable, constant and such things yet.
Is there a book out there that can enlighten me so I won’t irritate everyone here with my wacky coffee fueled questions?
Hopefully I didn’t come off as too irritated, my comment was more of a “think about it” approach.
Anyway, there is a manual for the AtomPro, which documents the basic functions mostly but isn’t really much of a teaching tool for programming the things. One thing that suffers is the lack of a handshake between the BAP and a host when using RS-232. If you are going wireless and have a TTL output from your module anyway you might be best served to use the hardware serial functions in the BAP. These require you use P14 and P15 as your serial lines. ALL of the other serial functions are bit-banged and thus suffer from the need to sit there and actually wait for a serial command, requiring some sort of handshake or risking the loss of serial data.
Once you have the hserial setup and functioning (a nice part about hserial using a separate set of dedicated pins is you can still use the built in rs-232 for programming and debugging while testing the hardware serial operation) you have to figure out if you plan on using single byte commands, strings or packets and write an appropriate handler.
Then, as wowy7 suggests, it eventually boils down to nested if-then-else statements or using the on…goto statements to vector operation based on some command value.
Not sure of your question, but if you need an example of code on the Atom, I suggest you generate a program using PowerPod. Make it for COM, and you’ll see how to receive a packet and decode it. You can then adapt it to take your packet (string).
EddieB, you didn’t seem irritated to me, I guess im just worried about bothering people. I respect everyones knowledge and am grateful for the help, I wouldn’t be able to get far without knowledgeable people like you guys.
The syntax manual really hasn’t given much help. I guess this is due to my lack of programming knowledge.
I will try the examples above and post what I come up with. I will try something simple with hyper terminal to see if I can make something work. I just ordered a ttl level shifter from sparkfun to allow me to use hserial instead serin.
Thanks tons and if you know of any readings to help me understand better, please let me know
I am not sure from your posts if the strings that you are receiving are of a fixed format or not. If it is fixed, it might be easy to read all of these values in with input modifiers.
for example if the first 2 bytes are characters, followed by a four 2 hex byte numbers you could do something like:
something like:
...
bIn1 var byte
bIn2 var byte
hIn1 var word
hIn2 var word
hIn3 var word
hIn4 var word
...
hserin 500, expd, [bIn1, bIn2, hex2 hIn1\2,hex2 hIn2\2,hex2 hIn3\2,hex2 hIn4\2]
...
Note without input modifiers I believe that hserin as well as serin and debug will only assign one byte of input to each variable, regardless of the size of the variable.
If your input does not have a fully fixed format, I would probably read the whole thing into a byte array using the string(STR) input modifier. Something like:
bMystr var byte(80)
...
hserin 500, expd, [str bMystr\80\13]
Then you will have to parse the strings and do the conversions…
Note: my example code may not be fully correct, but hopefully it might help give you some ideas…
Thanks for all the help guys, I wanted to thank you guys earlier but I have been swamped with school and work.
I haven’t been able to work on programming much, but this is what i have come up with
ENABLEHSERIAL
sethserial h9600,h8databits,hnoparity,h1stopbits
main
id var byte ; P char (of PC), identifing start of string and source
lx var word ; left stick x axis
ly var word ; left stick y axis
rz var word ; Right stick x axis
rr var word ; Right z rotation axis
btn var word ; 4 dig hex combo indicating button pressed
hserin 500, tmout, [id, hex2 lx\2, hex2 ly\2, hex2 rz\2, hex2 rr\2, hex4 btn\4]
if BTN = "$0000" then
low p8
else
high p8
endif
goto main
tmout
high p8
pause 100
low p8
pause 100
high p8
pause 100
low p8
pause 100
goto main
Its just a test to see if I can get the BAP to see the string, I get the following error: (LINE 21) : [TOKEN ] : Expected , or ]
Line 21 is the HSERIN line. I have played with it for 3 days and cant figure out my mistake.
I got this to compile…and it works. Don’t ask me how. I guess the sun shines on every dog’s ass once in awhile.
main
; STRING
id var byte ; P char (of PC), identifying start of string and source
lx var word ; left stick x axis
ly var word ; left stick y axis
rz var word ; Right stick x axis
rr var word ; Right z rotation axis
btn var word ; 4 dig hex combo for button
hserin 500, tmout, [id, hex2 lx, hex2 ly, hex2 rz, hex2 rr, hex4 btn]
if BTN = $0000 THEN
sound P9,[70\500]
pause 100
sound P9,[70\700]
pause 100
sound P9,[70\900]
pause 100
else
high p8
endif
goto main
tmout
high p8
pause 100
low p8
pause 100
high p8
pause 100
low p8
pause 100
goto main
I get the sound when I send hex 0000 with docklight.
gonna try labview next
That’s what I have been told so far. If I recall correctly, serin causes the program to stop until a command is received. I guess it would be better to allow it to run and execute without waiting for a command.
The big difference between hserin and serin is the hardware support. That is with HSERIN your pc program can send its output when it wants and the hardware on the H8 processor will receive the input and queue it up such that Atom Pro software can then read it when it wants. Where as serin is all software, so if your Atom Pro is not sitting in a SERIN wainting for the input from the PC and the PC sends the data, the data is lost.
Also as a side note, with the hardware serial port the hardware takes care of the bit timings so it is not effected by other stuff going on. Where as if for example your program uses interrupts, you may find that the serin and serout do not work properly at higher speeds sometimes as low as 9600 baud.
