hserin 100, main [flag] causing 18f24k22 to become unstabloe

[HenrikOlsson]

For the sake of testing, can you try moving the code in the getchar subroutine to the actual place where the GOSUB getchar is? In other words, don't use a GOSUB just place the actual code "in line" instead.

It's just a hunch but when you GOSUB getchar, where the HSERIN times out and jumps back to main you have an "unresolved" GOSUB/RETURN "pair". The number 27 happens to match the number of nested GOSUBs you can have on an 18F series, I think that's more than a coincidence.

/Henrik.

[Ioannis]

Timeout from a subroutine getchar to main is wrong.

You should do it like this:

getChar


'Receive a character, if no character within 100ms, then goto main
hserin 100, exit_getchar, [flag]
pause 100
hserout ["received a character", 13]
' if char[0] = "U" then
' HSerout ["received a 'U'", 13]
'Receive the remainder of the message
' hserin [STR char[1]\9]
' hserout ["received 9 more characters",13]
' hserout [str char\10]
'array char[] should now hold all 10 bytes of the message from Elo
' endif

exit_getchar:

return

Of course this will not start over from main, but if you need this, then set a flag in the subroutine that Hserin timed out and then jump to main (resetting the flag first).

Ioannis

[pedja089]

You are right.
He uses GOSUB and when times out, RETURN isn't executed. And it will jump with GOTO from HSERIN function to main.
Other workaround is

getChar:
'Receive a character, if no character within 100ms, then goto main >> IF you use goto main stack overflow, because RETURN isn't executed. 
hserin 100, GetCharError, [flag]
pause 100
hserout ["received a character", 13]

GetCharError:
return

[svjohngalt]

Thank you and I changed the gosub to simply goto which works. I would ask, where is the maximum number of nested gosub routines documented?

Again, thanks

George