Getting Stuck in loop

[mister_e]

There's a strong smells of ...
http://www.picbasic.co.uk/forum/showthread.php?t=561

[Frozen001]

The complete code is pretty long.... but here are the settings I am using. The code I posted prior is first few lines I have to run in the code. After that is is just decoding the data so I can send it to a display. The 3 8-bits of data that I read from PortJ are characters that used to be sent to a 16segment display, which I am working to replace with a modern dot-matrix dispaly.

' Genenal Register Settings, Port Settings and System Definitions



CMCON = 7								' Disables the Comparitor Pins
ADCON1 = 15								' Disables the A/D Converter Pins
TRISA = $FF							' Define Port A(0-7) as Input 
										'      (Host TTL inputs, RA7 unused) 
TRISB = $E0								' Define Port B(0-4) as Output
										'      (RB0-4 Character Output; RB5-7 are programming port)                                                 
TRISC = $00								' Define Port C(0-2) as Outputs 
										'      (Left=C0; Middle=C1; Right=C2 displays)
TRISD = $00								' Define Port D(0-7) as Output 
										'      (Character Data Outputs)
TRISE = $FF								' Define Port E(0-7) as Inputs 
										'      (Ext. Keyboard Inputs)
TRISF = $F0						' Define Port F(0-3) as LED Outputs, F(4-5) as 
										'       Test SW inputs and F(6-7) as Display Int and Kbd Int I/O
TRISG = $F0								' Define Port G0 as I/O for Reset, G1-3 as Rd/Wr/Fl Outputs
TRISH = $FF								' Define Port H(0-7) as Inputs
TRISJ = $FF								' Define Port J(0-7) as Inputs (Host TTL inputs)                        
                                                                         
Define OSC 20							' Sets Oscillator Speed at 20Mhz
Define BUTTON_PAUSE 100					' Sets Button Debounce time to 100 ms
Define I2C_SLOW 1						' Sets I2C Speed to 100KHz

[Bruce]

Stuff you want to REPEAT needs to be in between the REPEAT
UNTIL.

Like

REPEAT
this
UNTIL this

Not

REPEAT
UNTIL this
do this

[Frozen001]

Stuff you want to REPEAT needs to be in between the REPEAT
UNTIL.

Like

REPEAT
this
UNTIL this

Not

REPEAT
UNTIL this
do this

I am using the repeats as delays so the pic waits for the data basically. The data being sent comes in as 3 seperate 8-bits in sequence. The data is read off of PortJ. The data always comes after PortA.5 goes low. Ant it is always in a specific order. If I miss any 1 of the three I cannot tell what the actuall character is.

[mister_e]

How neat the signal on PORTA.5 is? Where this signal come from?

[Frozen001]

How neat the signal on PORTA.5 is? Where this signal come from?

Looking at the signal in question on an o-scope, It looks pretty clean to me. It is connected to a 100K pull-up to 5V. The transition from high to low does have some ringing , that lasts about 90nS give or take, but the peaks are all < 0, so it should still be seen as a low.

[mister_e]

Reduce it!!! Let's say ~1-10K pull-up.

AND, wait a few Usec after you detect the falling edge...

[Acetronics2]

Hi,

1) @20Mhz ... min Pauseus is ... 3µs !!!

2) UNTIL NOT PortA.5 is much quicker than UNTIL PortA.5 = 0

3) PortF.6 = 1 is much quicker than HIGH PortF.6

4) Instead of Repeat - Until NOT PortA.5, try While PortA.5 - Wend ...

Alain

[mister_e]

In fact, you should use LATF.x instead of PORTF.x ...
Alain, OP says WHILE:WEND didn't work.. not sure why... sounds odd...

[Acetronics2]

In fact, you should use LATF.x instead of PORTF.x ...
Alain, OP says WHILE:WEND didn't work.. not sure why... sounds odd...

a good point for a " not so clean" signal ...

While PortA.5 : Wend just gives

BTFSC Porta,5
GOTO $-1

...

asm is really useful, sometimes !!! lol

Alain

[Frozen001]

Hi,

1) @20Mhz ... min Pauseus is ... 3µs !!!

2) UNTIL NOT PortA.5 is much quicker than UNTIL PortA.5 = 0

3) PortF.6 = 1 is much quicker than HIGH PortF.6

4) Instead of Repeat - Until NOT PortA.5, try While PortA.5 - Wend ...

Alain

Couple of things... My code as it is shown works for the most part as long as the loop does not get hung up.


1) Made the change, seems to work as before....

2) Made change code works as it did before

3) I will randomly miss characters, changed it back to what I originally had

4) Made change, I no not get any characters.