What is wrong & where - 16F877A+U2 USB programmer

[Megahertz]

Hi, I am unable to make any of my PIC work when I program it with my U2 usb programmer.
I compile it with MPLAB>>PBP.
Programs as simple as HIGH portb.7 : pause 2000 : low portB.7 are not working as well though the programmer shows that it got programmed fine.

Many times I have to disconnect/reconnect the wire of the USB programmer because of the error messeges such as "Device Not Blank........" or "Device does not match......" even though the correct device is selected. Is my programmer at fault?
Can someone please help me to know where the problem is? Thanks

[Darrel Taylor]

With so little information, there's no way to know.

Have you verified the items on the ICSP page?

In-Circuit Serial Programming (ICSP)
http://melabs.com/support/icsp.htm

Have you set your configs?

Specifying configuration bit settings in PICBASIC PRO™ programs.
http://www.melabs.com/support/config_defaults.htm

Have you disabled the Analog inputs?

All Digital
http://www.picbasic.co.uk/forum/showthread.php?t=11100
<br>

[rsocor01]

Megahertz,

I have a U2 USB programmer and it works great. Can you post your code? Can you post the programmer PIC settings? Are you doing ICSP?

I ussually get the "Device does not match......" message when the PIC is not receiving any power.

Robert

[Megahertz]

Here is my code:

Include "modedefs.bas"
INCLUDE "DT_INTS-14.bas" ' Base Interrupt System
INCLUDE "ReEnterPBP.bas" ' Include if using PBP interrupts
DEFINE NO_CLRWDT 1
DEFINE OSC 4 ' OSCCON defaults to 4MHz on reset

@ __CONFIG _XT_OSC & _WDT_OFF & _PWRTE_ON & _CP_ALL & _BODEN_ON & _CPD_ON

PAUSE 100
LED VAR PORTB.6
F1 var Bit
F2 var Bit
F3 var Bit
S1 var bit
S2 var bit
S3 var bit
i var byte

DEFINE DEBUG_REG PORTB
DEFINE DEBUG_BIT 7
DEFINE DEBUG_BAUD 2400
DEFINE DEBUG_MODE 1

DEFINE DEBUGIN_REG PORTA
DEFINE DEBUGIN_BIT 0
DEFINE DEBUGIN_MODE 1

PAUSE 50
ADCON1=7
CMCON=7
OPTION_REG=%10000111
TRISA=%000001
PORTA=0
TRISE=%000
PORTE=0
TRISB=%00000000
PORTB=0
TRISC=%00001111
PORTC=0
TRISD=%00000011
PORTD=0
CCP1CON=0
@ ERRORLEVEL -306

F1=0 : F2=0 : F3=0 : S1=0 : S2=0 : S3=0

main:
high LED: LED=1 : PAUSE 2000

ASM
INT_LIST macro ; IntSource, Label, Type, ResetFlag?
INT_Handler TMR1_INT, _ToggleLEDF, PBP, yes
INT_Handler TMR0_INT, _ToggleLEDS, PBP, yes
endm
INT_CREATE ; Creates the interrupt processor
ENDASM
T1CON = $31 ; Prescaler = 8, TMR1ON
@ INT_ENABLE TMR1_INT ; enable Timer 1 interrupts
@ INT_ENABLE TMR0_INT ; enable Timer 1 interrupts'


while 1
Start:

M1A:
If PortC.0=0 then

mmm:
for i=1 to 30
DEBUG "MT3",2,10
Pause 10
next i

M1S:
DEBUGIN 3000,mmm,[WAIT("MT3",2,"S")]
F1=1 : PAUSE 1500

DEBUGIN [WAIT("MT3",2,"C")]
F1=0 : S1=1 : PAUSE 1500
endif

M1D:
If PortC.1=0 then
mm:
for i=1 to 30
DEBUG "MT3",2,"D"
Pause 10
next i
DEBUGIN 3000, mm,[WAIT("MT3",2,"D")]
F1=0 : S1=0 : PortA.0=0 : PAUSE 1000
endif
wend
'---[TMR1 - interrupt handler]--------------------------------------------------

ToggleLEDF:
If F1=1 then Toggle PortD.2
If F2=1 then Toggle PortD.3
If F3=1 then Toggle PortC.4
@ INT_RETURN

'---[TMR2 - interrupt handler]--------------------------------------------------

ToggleLEDS:
TOGGLE LED
If S1=1 then Toggle PortD.2
If S2=1 then Toggle PortD.3
If S3=1 then Toggle PortC.4'
pause 100
@ INT_RETURN

I have to try many times by disconnecting/reconnecting the USB cable so that my board come to Green LED (Ready). 95% of times there is an error message. I am unable to do anything smoothly using this board, I do not know if I am doing somethign wrong or the board is faulty.

I am now trying to upload this code and errors is "Target Device does not match the selected device", even though 16F877A is selected on Programmer window.
Also with the ones I programmed before - My LED does not GLOW for 2 seconds when the code starts. PIC seems to keep resetting itself - The reason is that the LED starts flickering.

I am not programming the PIC while it is in its circuit. I am using the 40PIN connector with the USB programmer.

But First thing first, please help me solve the programming board problem, so I can firstly start programming smoothly. I have attached the programmer settings screenshot. Please let me if any more information is needed. Thanks a lot.

[Darrel Taylor]

I am not programming the PIC while it is in its circuit. I am using the 40PIN connector with the USB programmer.

Which one of the 40-pin adapters do you have?

http://store.melabs.com/graphics/00000001/840z.jpg - http://store.melabs.com/graphics/00000001/40-28PIN_ADPT.JPG

If it's the one on the left, is it connected properly for a 40-pin device.

http://www.pbpgroup.com/files/840z-40.JPG

[Megahertz]

Yes it is the one on the left. Thanks

[rsocor01]

Megahertz,

Are you setting the chip in the right position like Darrel is showing you in the picture above? Pin 1 has to be in the right position. Also, try using different USB ports in your computer and even a different computer.

Robert

[Megahertz]

Megahertz,

Are you setting the chip in the right position like Darrel is showing you in the picture above? Pin 1 has to be in the right position. Also, try using different USB ports in your computer and even a different computer.

Robert

Apologies for the delayed reply. Yes I am setting the chip the right way. I also tried on different computer but red led flashes on the board. I have to reconnect the USB cable around 4-5- times before it turns green and then programs the chip. Then most of the times the same story again for the next chip I want to program.