bootloader does not work..
hello you all...
I'm trying to make the Tiny bootloader to work but all I get is the same error:
Connected to \\.\COM1 at 115200
Searching for PIC ...
pic sending unknown data: "K" <> F0h=ð
Check baudrate & Start Write while PIC is not sending serial data (e.g. in reset)
i've tried changing baudrate and etc.. i'm using a 20mhz xt, pic 16f88 ... does anyone can help me?
thanks in advance...
Sylvio
Are you using a max232 device?
Hi supratic,
You mention modifying the code. What were your modifications? The PIC16F877A should work straight out of the box, no modifications required, with the hex called tinybld_16F876A_20MHz.HEX for 20 mhz. One thing you don't mention is a MAX232 device connected to your pic chip. You will need it on the PIC16 devices to invert your signal and modify their levels for your computer to "hear" correctly.
If you were using a PIC18, you could modify the code so you did not need a max232 device. http://www.picbasic.co.uk/forum/show...2538#post82538
Walter
Re: bootloader does not work..
hi,
i hope now still can have genius here to help me solve my problem.I have built a bootloader and using the tiny bootloader software.and i hv face the same problem as here.the bootloader showed this
Connected to \\.\COM4 at 19200
Searching for PIC ...
pic sending unknown data: "K" <> 0h=
Check baudrate & Start Write while PIC is not sending serial data (e.g. in reset)
ERROR!
I'm using PIC16f877a,usb serial converter_RS232 9pin,max232 ic.i have followed schematic i google up but still cant work.hope you can help me.
Re: bootloader does not work..
Hi bmmilk, Can you let me know is it a blank chip? A blank chip is something whose program memory is completely erased. It could be a brand new IC or somebody has erased it purposefully. Also can you attach your schematic...
Re: bootloader does not work..
Re: bootloader does not work..
Quote:
Originally Posted by
supratik
Hi bmmilk, Can you let me know is it a blank chip? A blank chip is something whose program memory is completely erased. It could be a brand new IC or somebody has erased it purposefully. Also can you attach your schematic...
Thank for you reply.I have tried a chip i purposely erase and also a chip with program inside.but still cannot work.when i tried to write flash the program showed the words i posted in the previous post.
http://highschoolrobots.com/serial.aspx
this is the schematic i follow to build the bootloader.what can i do with my problem?
Re: bootloader does not work..
What speed crystal are you using on your PIC16F877a, and which hex file are you using? Do you have a schematic of your PIC16 chip setup?
Re: bootloader does not work..
Quote:
Originally Posted by
ScaleRobotics
What speed crystal are you using on your PIC16F877a, and which hex file are you using? Do you have a schematic of your PIC16 chip setup?
I'm using 4MHZ crystal. the hex file is tinybld_16F876A_04MHz.
ooppss,i dont have schematic of my pic setup.but it works well when i use a programmer to program instead of trying to build a bootloader.
Re: bootloader does not work..
Hi bmmilk,
Quote:
i dont have schematic of my pic setup.but it works well when i use a programmer to program instead of trying to build a bootloader.
So, when you program it with a programmer, you can get you code to work with your setup?
I have used the Tiny Bootloader on the same chip, with a RS232 to USB converter and had it work for me. It sounds like you are doing everything else right, so I suspect the wiring. How about a picture of your setup?
Re: bootloader does not work..
Quote:
Originally Posted by
ScaleRobotics
Hi bmmilk,
So, when you program it with a programmer, you can get you code to work with your setup?
I have used the Tiny Bootloader on the same chip, with a RS232 to USB converter and had it work for me. It sounds like you are doing everything else right, so I suspect the wiring. How about a picture of your setup?
Quote:
Originally Posted by
ScaleRobotics
Hi bmmilk,
So, when you program it with a programmer, you can get you code to work with your setup?
I have used the Tiny Bootloader on the same chip, with a RS232 to USB converter and had it work for me. It sounds like you are doing everything else right, so I suspect the wiring. How about a picture of your setup?
@ScaleRobotics:
ya when i program with an external programmer my code can function with the hardware.I hv posted 4 pictures of my connection of max232 and also pic16f877a.i doubt that if my connection is correct is it my usb serial converter spoil or cant work.i dont know.
here are the pictures,feel free to help me check ya...thank you a lot^^
http://bmmilk.blogspot.com/2011/10/blog-post_15.html
1 Attachment(s)
Re: bootloader does not work..
Thanks Sylvio,
It looks like TX pin 11 of the Max232 chip (red wire) is going to the RX pin of the PIC chip. In this case RX should go to RX and TX should go to TX.
Attachment 6059
Re: bootloader does not work..
Quote:
Originally Posted by
ScaleRobotics
Thanks Sylvio,
It looks like TX pin 11 of the Max232 chip (red wire) is going to the RX pin of the PIC chip. In this case RX should go to RX and TX should go to TX.
Attachment 6059
ya,I changed the connection.but now the bootloader show this when i tried to write flash
Connected to \\.\COM4 at 9600
HEX: 3052 days old, INHX8M,16Fcode+cfg, total=200 bytes.
Searching for PIC ...Not found,
ERROR!
so what can i do with this?thank you
Re: bootloader does not work..
bmmilk,
Can you check the following things
1. You are supposed to use the programmer to download the tinybld_xxxxx.hex file. Once it is done the chip will learn how to talk with tiny bootloader using serial port. After that you should be able to use serial port to download your own program (try with some blinky program).
2. If you are using electrolytic capacitor for MAX232 check the polarity of the caps. A single reverse caps can create those problems.
3. PIN 11 of MAX232 should go to RC6 and PIN 12 to RC7 of uC.
4. PIN 13 and 14 of MAX232 should go to Tx (pin 3) and Rx (pin 2) of serial port (DB9).
5. Make sure you have the right baud rate. It should be defined in the .asm file.