Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Register Log in

[SOLVED] 18F4550 bootloader problem

Status
Not open for further replies.
varunme

varunme

Advanced Member level 3
Advanced Member level 3
Joined
Aug 10, 2011
Messages
741
Helped
17
Reputation
36
Reaction score
17
Trophy points
1,318
Activity points
5,765
18F4550 when programmed with microchip bootloader firmware and used with
**broken link removed**
board , when connected to USB , message shows , usb device not recognized and shows unknown device in device manager , I am using K182 programmer from Kitsrus for programming the PIC , I didn't changed anything including fuse settings from the original bootloader , what can be the reason for not functioning ?
 

hi,
Try to check if the oscillator is on!
Measured on pins 13 and 14 and see if you have approximately 2V.
If you have not: change the 2 capacitor or the quartz.
Measured on pin 1 and see if you have 5V.
 
  • Like
Reactions: varunme

    varunme

    varunme

    Points: 2
    Helpful Answer Positive Rating
pin 13 is giving 0.98V and pin 14 is giving 2.14V and pin 1 is giving 1.64 V
 

Hi!

The voltage on pin 13 is not good ! change or verify c3 !

remove C15 and verify R1 ! On C1 you have 5 V ? On pin 1 you need to have 5V.
 

hi all,

varunme did you got it working? if yes, can you please let me also how you solved it.

members i am also having a similar kind on issue, if you wish please take a look at my issue also (https://www.edaboard.com/threads/224034/)

thanks
 

Not yet , devil6600 , i will definetly inform you dear once i rectify it :smile:
 

if you are using the same schematics as the one mentioned (olimex circuit), then I think you need to keep RB4 button pressed or short to ground while connecting the board to the USB port of PC. You need to burn the bootloader with a hardware programmer, later your could flash the chip with PDFUSB from microchip.
 

RB4 shorted at connection time and inconjunction with reset switch also tried
 

There are only few possibilities here:

1) USB D+/D- have been connected in reverse.

2) correct PIC driver has not been installed on PC

3) long shot boot loader has not been installed properly.

my hunch is no 1.
 

I cannot install the driver as i connect the board , message says unknown device
 

pmar_kpj said:
Hi!

The voltage on pin 13 is not good ! change or verify c3 !

remove C15 and verify R1 ! On C1 you have 5 V ? On pin 1 you need to have 5V.
Click to expand...

C1 is giving 4.54V

---------- Post added at 09:32 ---------- Previous post was at 09:21 ----------

D+ and D- are fine

---------- Post added at 10:01 ---------- Previous post was at 09:32 ----------

 the MCLR (pin1) now shows 5V (it was a mistake by me that the power adapter wasnt connected , now connected it and shows 5V in MCLR)
C3 changed , but the pin 13 , shows only 0.80V
 
Last edited:

in circuit C1 and R1 are fine, should i remove and check ?
thanks
 

Hi varunme,

What is the exact bootloader you are using? Can you provide a link to it on the Microchip Website?

BigDog
 

I tried almost all Bootloaders and the USB firmware without bootloader as well
from Microchip
**broken link removed**

thanks
varnme
 

Hi!

try to burn this : **broken link removed** ! if led blinking is good!
 

I have tried this and programs created by me to check each ports , all are working except the firmwares using USB
 

what is the value of capacitor you are using at vusb pin?

try the attached hex file, it should blink led on porta.0 (pin2) 5 times a second, this will confirm pic is running at proper speed.
 

Attachments

  • test.zip
    277 bytes · Views: 91
Last edited:

c5 marked as 0.1 and is disc capacitor , the code (attached) works correct
 

hi !
i attach a CCD Demo from MCHPFSUSB v2.2 USB Framework compiled and tested on mai board with 18f4550.
Please burn a "USB Device - CDC - Basic Demo - C18 - PICDEM FSUSB.hex"!
 

Attachments

  • USB Device - CDC - Basic Demo.zip
    126.7 KB · Views: 85

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top