Frequency Counter

[Asmith]

To Skimask:
I tried out the code you gave me and it did write through the EEPROM like it was suppose to. I re-wrote the code I had and it gives me 00 00 when I do not move any of the inputs around at all if I pull the Pulse Wire in and out of ground it seems to give me random values not how many time I pull it in and out, it does seem kind of close though. The code is posted below if you see a problem with it. Thanks for your help btw. I've been working on this all day now and can't seem to get any repeatability.

*************************************************
@ DEVICE PIC12F683, INTRC_OSC_NOCLKOUT
@ DEVICE PIC12F683, WDT_ON
@ DEVICE PIC12F683, PWRT_ON
@ DEVICE PIC12F683, MCLR_OFF
@ DEVICE PIC12F683, BOD_ON
@ DEVICE PIC12F683, CPD_OFF
@ DEVICE PIC12F683, PROTECT_OFF

TRISIO = %11111111

Location var WORD

Mult_Count VAR BYTE

Was_Low VAR BIT

Pulse var gpio.3
Direction VAR gpio.5

Mult_Count = 0
Location = 0
Was_Low = 0

PAUSE 500

main:

IF Pulse = 1 AND Was_Low = 0 THEN
IF Direction = 1 THEN
Mult_Count = Mult_Count + 1
ELSE
Mult_Count = Mult_Count - 1
ENDIF
Was_Low = 1
ENDIF

IF Pulse = 0 THEN
Was_Low = 0
ENDIF

IF Mult_Count = 10 THEN
Location = Location + 1
Mult_Count = 0
ENDIF

IF Mult_Count = -10 THEN
Location = Location - 1
Mult_Count = 0
ENDIF

WRITE 0, Location.Byte1
WRITE 1, Location.Byte0
GOTO main
end

*********************************************

To mister_e:

I can easily change the clock to 8MHz, I should have done that in the first place. The PWM signal I have done as well, using C code on this chip, and it works pretty nicely. I haven't used the timers before though, although I would really like to go this route with this. My only concern would be I need to be able to count up and down and I'm unsure if can I do so with these Timers. Maybe one way to do so would be to call a interrupt when a direction change is seen and save the timer value before resetting it to 0. Then do the math to another variable with the true position value. I'm gonna start reading on it while I'm still at work. Thanks for the idea it sounds like the best way to go. If you have any advice for going about it let me know. Thanks again.

Anthony

[Bruce]

See if this helps;

CMCON0 = 7
ANSEL = 0

Comparators & A/D are enabled by default on power-up. To use some pins for
digital I/O, you need to disable these.

[Archangel]

To Skimask:
I tried out the code you gave me and it did write through the EEPROM like it was suppose to. I re-wrote the code I had and it gives me 00 00 when I do not move any of the inputs around at all if I pull the Pulse Wire in and out of ground it seems to give me random values not how many time I pull it in and out, it does seem kind of close though.
Anthony

It might be working and counting multiple switch closures due to bouncing switch contacts (noise).

[Ioannis]

IF Mult_Count = -10 THEN
Location = Location - 1
Mult_Count = 0
ENDIF

Are you sure that PBP can do negatives???

Ioannis

[Asmith]

Bruce:
Thank you I did forget to set up those two registers. I will fix that.

Joe:
I'm using a function generator on the input with a scope on it as well and there is no bouncing on the pin. In the end it will be from a hall effect switch which also should not have any bouncing.

Ioannis:
I believe PBP will do negative numbers, Location should never be a negative number anyways as 0 would be the lowest number of counts you can have it will be zero we it is set up.

I think I'm going to try and use the internal timer which I haven't been able to work on it much as work has me burried. I did have some time to write out some code. I will post is below, if you guys would like to comment on it I would appreciate it. It might be a little chopy at the moment though.

************************************************** *****
@ DEVICE PIC12F683, INTRC_OSC_NOCLKOUT
@ DEVICE PIC12F683, WDT_ON
@ DEVICE PIC12F683, PWRT_ON
@ DEVICE PIC12F683, MCLR_OFF
@ DEVICE PIC12F683, BOD_ON
@ DEVICE PIC12F683, CPD_OFF
@ DEVICE PIC12F683, PROTECT_OFF

'* Hardware Setups *

INTCON = %10001000
PIE1 = %00000000
PIR1 = %00000000
OSCCON = %01110000

'* I/O Pin Descriptions Below *
'* PIN 1 - VDD - 5V *
'* PIN 2 - T1CK1 - Input - Pulses from Hall Effect *
'* PIN 3 -
'* PIN 4 - GP3 - Input for the direction of the Hall Effect *
'* PIN 5 - CCP1 - PWM Output to the Analog converter *
'* PIN 6 -
'* PIN 7 -
'* PIN 8 - VSS - Ground *

TRISIO = %00101000
WPU = %00000000
IOC = %00001000

'* Timer Setup *
T1CON = %00100111



Location var WORD

Mult_Count VAR BYTE

Was_Low VAR BIT

Pulse var gpio.3
Direction VAR gpio.5

Mult_Count = 0
Location = 0
Was_Low = 0

PAUSE 500

main:


GOTO main
end

************************************************** ***

[skimask]

Ioannis:
I believe PBP will do negative numbers, Location should never be a negative number anyways as 0 would be the lowest number of counts you can have it will be zero we it is set up.

Sure, PBP and assembly both will do negative numbers, but they won't show up the way you want them to...i.e.:

5 - 6 = -1, but PBP will show 255 (for a byte variable), 65535 (for a word variable).

You're going to want to add something like this to your program in post #4:

main:
IF Pulse = 1 AND Was_Low = 0 THEN
IF Direction = 1 THEN
Mult_Count = Mult_Count + 1
ELSE
if mult_count > 0 then mult_count = mult_count - 1
ENDIF
Was_Low = 1
ENDIF
...............

IF Mult_Count = -10 THEN(statement won't work the way you want it to in PBP)
Location = Location - 1
Mult_Count = 0
ENDIF

[Archangel]

Bruce:

Joe:
I'm using a function generator on the input with a scope on it as well and there is no bouncing on the pin. In the end it will be from a hall effect switch which also should not have any bouncing.




************************************************** ***

It was worth checking.
JS