pulsin followed by serin2 problem

I am measuring pulse length.This routine works fine as long as I comment out serin2 command. It appears that pulsin command is affected or timing when I add serin command. I no longer decode valid pulse that I am monoriting with a scope. Any Suggestions, I have tried numerous delays etc.

Thanks in Advanced
Stuck and sleepless












wait_for_t0:

if portb.0= 0 then wait_for_t0 ' loop until rssi goes high

pulsin portd.4,1,PLENGTH1 ' MEASURE TIME C2 IS HIGH AND STORE
IF PLENGTH1 > 255 AND PLENGTH1 < 270 THEN COUNTPULSes ' 42 usec error allowed


serin2 b2,16780,1000,wait_for_t0,[WAIT ("$$"),cmnd] ' get command wait $$ timeout 1 secs added
GOTO wait_for_t0

wait_for_t0:

if portb.0= 0 then wait_for_t0 ' loop until rssi goes high

pulsin portd.4,1,PLENGTH1 ' MEASURE TIME C2 IS HIGH AND STORE
IF PLENGTH1 > 255 AND PLENGTH1 < 270 THEN COUNTPULSes ' 42 usec error allowed






Pulsin, you have a "1". that means you are waiting for a HIGH pulse in order to get out of your loop:

Since the high is already over with, you are not measuring that first "Pulse" You are losing that pulse and measuring the next one.



Dwayne

Dwayne,

I use Portb.0 as key and Portd.4 to measure pulse. I am decodeing apulse stream from a radio to determine a time zero " time begins now pulse" the first tone is 1khz for approx. 10 cycles and changes to 2khz ,I detect this change and output a pulse for time begins now. I t was working fine until I added the serin2 command. I need this for a command structure input via the telemetry link. I have lots of time between keys 2 to 6 secs


Thanks again

Scott

Hello Scott,

Scott>>
wait_for_t0:

if portb.0= 0 then wait_for_t0 ' loop until rssi goes high

pulsin portd.4,1,PLENGTH1 ' MEASURE TIME C2 IS HIGH AND STORE
IF PLENGTH1 > 255 AND PLENGTH1 < 270 THEN COUNTPULSes ' 42 usec error allowed


serin2 b2,16780,1000,wait_for_t0,[WAIT ("$$"),cmnd] ' get command wait $$ timeout 1 secs added
GOTO wait_for_t0<<

Try changing it to this then:

Code:

---

wait_for_t0:

if portb.0= 0 then wait_for_t0 ' loop until rssi goes high

pulsin portd.4,1,PLENGTH1 ' MEASURE TIME C2 IS HIGH AND STORE
IF PLENGTH1 > 255 AND PLENGTH1 < 270 THEN COUNTPULSes ' 42 usec error allowed

receivedata:
serin2 b2,16780,1000,receivedata,[WAIT ("$$"),cmnd] ' get command wait $$ timeout 1 secs added
GOTO wait_for_t0

---

This way, if your Serin times out before it is supposed to , it will re-initialize itself and wait for your data again.

I am taking this on assumption that you said there was plenty of time between the two signals...

If you want, you could put a counter and if the counter goes above 10 loop back to the wait_for_t0.

Since I don't fully understand your project... I apologize if I read you wrong.

Dwayne

INCLUDE "MODEDEFS.BAS"
Define OSC 20 '20 meg clock`
'define PULSIN_MAX 26000 ' MAX TIME TO READ PULSE 800US added
' Define LCD connections

B2 var PORTB.2
B1 VAR PORTB.1 ' FIRE LINE OR DECODED T"0"
CNT VAR BYTE ' VARIBLE FOR COUNT OF PULSES
PLENGTH1 VAR word ' VAR FOR FREQ MEASURE OF C2 first tone
C2 var portc.2
D4 var portd.4 'input pin
plength2 var byte ' var for second freq
ffid var word ' shot #
cmnd var byte ' var for command number
gosub radio_pwr_on
main: input portb.0
input portd.4
gosub xmit_off
gosub wait_for_t0







wait_for_t0:

if portb.0= 0 then wait_for_t0 ' loop until rssi goes high

'
pulsin portd.4,1,PLENGTH1 ' MEASURE TIME C2 IS HIGH AND STORE
IF PLENGTH1 > 255 AND PLENGTH1 < 270 THEN COUNTPULSes ' 42 usec error allowed
gosub get_comnd

' made into sub routine get_cmnd
'serin2 b2,16780,1000,wait_for_t0,[WAIT ("$$"),cmnd] ' get command wait $$ timeout 1 secs added
'HSEROUT ["debug command = ",dec2 cmnd,13,10]
GOTO wait_for_t0

COUNTPULSES: COUNT portd.4,8,CNT ' COUNT PULSES FOR 10 MILISECS
IF CNT > 6 and cnt < 9 THEN DETECT2
'HSEROUT [" debug count = ",DEC3 cnt,13,10]
GOTO wait_for_t0

DETECT2:
pulsin portd.4,1,PLENGTH2 ' MEASURE PERIOD HIGH
IF PLENGTH2 > 115 AND PLENGTH2 < 130 THEN FIRE ' 20 usec error

GOTO main

FIRE: LOW B1


HIGH B1
PAUSE 10
LOW B1
ffid = ffid + 1
if ffid =65535 then ffid = 0 ' reset ffid id exceeds word size
HSEROUT ["fired ok ffid # =",dec5 ffid,13,10]
HSEROUT ["debug fired plength 1 =",DEC3 plength1,13,10]
HSEROUT ["debug fired plength 2 =",DEC3 plength2,13,10]
HSEROUT ["debug fired count = ",DEC3 cnt,13,10]
goto main


Radio_pwr_on: high portd.0
pause 10
low portd.0
pause 500 ' wait for power to come up
return

Radio_pwr_off: high portd.1
pause 10
low portd.1
return

xmit_off : high portd.2
pause 1
return

xmit_on : low portd.2
pause 50
return

get_comnd: serin2 b2,16780,1000,wait_for_t0,[WAIT ("$$"),cmnd] ' get command wait $$ timeout 1 secs added
HSEROUT ["debug command = ",dec2 cmnd,13,10]
return






command_decode: Select case cmnd
case 1 ' command #1 T0 mode
gosub xmit_on
serout2 portc.2,84,["Buoy is in fire Mode",13,10]
gosub xmit_off
gosub wait_for_t0


case 2
gosub power_on_sbc ' command #2 turn on external power to device #1 SBC power on
gosub xmit_on
serout2 portc.2,84,["SBC power is on",13,10]
gosub xmit_off


case else
return

End select


power_on_sbc: high portb.5
return

The problem is not with the serin2 command. It is the pulsin command with the addition of serin2 command. Everything was working until I added sub routine get_cmnd. The correct pulse stream is still coming in etc. It is not decoded properly at pulin command .Sorry for the mess of commented out code I have been trying everything I can think of.


thanks

Scott

Hello Scott...

Thats it...

you are going SUBROUTINE and instead of branching to the END of the subroutine, you are branching OUT of it with a goto statement!!!

THAT IS WRONG! (Cruising for a bruising.)...Maybe some others can verify ths for me and you.

If I were you, I would *always* branch to the Return statement when you are into a Subroutine. Helps clear the stacks and all that good stuff. If I were to place my bet, it would be located here.

Dwayne

edit:
Took another quick look at your code...(very quick)

Code:

---

case else
return

End select

---

I am not sure about this.. Its been a while.. But usually you want your return AFTER the end select...

It's amix of many things. One thing scratch my brain

Code:

---

main:
    input PORTB.0
    input PORTD.4
    gosub xmit_off
    gosub wait_for_t0

wait_for_t0:
    if portb.0= 0 then wait_for_t0 ' loop until rssi goes high

---

Take care of the Gosub / Return use. It's amazing how fast your program can behave weird when using few nested gosubs...

the following snip is the source of your headache

Code:

---

wait_for_t0:
    if portb.0= 0 then wait_for_t0 ' loop until rssi goes high
   
    pulsin portd.4,1,PLENGTH1 ' MEASURE TIME C2 IS HIGH AND STORE
    IF PLENGTH1 > 255 AND PLENGTH1 < 270 THEN COUNTPULSes ' 42 usec error allowed
    gosub get_comnd
        ' made into sub routine get_cmnd
        'serin2 b2,16780,1000,wait_for_t0,[WAIT ("$$"),cmnd] ' get command wait $$ timeout 1 secs added
        'HSEROUT ["debug command = ",dec2 cmnd,13,10]
    GOTO wait_for_t0
    '
    '
    '   
get_comnd:
    serin2 b2,16780,1000,wait_for_t0,[WAIT ("$$"),cmnd] ' get command wait $$ timeout 1 secs added
    HSEROUT ["debug command = ",dec2 cmnd,13,10]
    return

---

easy to overflow the stack with this

Hi, Steve

have a look there : http://www.picbasic.co.uk/forum/showthread.php?t=1952

I had a similar problem there, It seems that having GOTO',s outgoing and coming back to sub's did not work very well ...
IF - Then, placed after the GOTO line ( in the sub ...) tests had always "yes" as a result ...
This was added to a page boundary crossing ... ( worked on a 628, but no more on a 648 !!! )

The solution for me was to place the program bits in good order ( all sub's at the end of the program and no "main" lines after ...

Alain