Why use a bootloader?

[mister_e]

As you're using a 18F

@    RESET

should do. bootloader mode get out pretty fast of there, not like Tiny (which I can recall something like ~1 Sec before getting out)

[Fredrick]

Hmm... why does´t microloader work...

When i press the program button the message "Please restet the PIC in order to access bootloader process"

I press the reset button on the PCB (MCLR) and nothing happens..... i have to close the message window then the programming starts. is that normal?

Should´t the programming starts when i press the MCLR button?

[Fredrick]

Another thing with Microloader and Microcode studio plus is the way i have to set the COM port.

(I use a virutuel COM port, not a real one.)

If i run only the Microcode loader i can´t set the COM port at all, the dropdownlist is empty and "gray". if i run Microcode studio i can set the COM port via the ICD toolbar but when i use my PIC18F2550 i can´t so to set the right COM port i have to change the device to 16F628A and then change the COM port and then change the device back to 18F2550.

[HenrikOlsson]

Hi Fredrick,
The best way to do it is to add the connection to MCLR as per Steves previous message. It is rock-solid, I've been using ot for years. If you don't want to do that try holding down the Reset-button, click compile and program and when the program window pops up quickly release the reset-button.

The virtual COM port MIGHT be a problem, I've never had any problems personally but I've read about bad drivers and strange chip-sets in some of the cheap USB<->RS232 dongles.

[Fredrick]

This is the way my hardware looks like


So i think that i just have to sold a wire from DTR pin from the FTDI chip to MCLR pin on the PIC with a 100ohm resistor in serie to get the software reset in microloader to work, right?

[mister_e]

In theory yes it has to work. Now the small timing issue you may have is the latency of the USB to serial converter. But I do remember to have successfully used some in the past.

Finger crossed.

One thing I would suggest to be really careful about is if you use ICSP later... MCLR have to go somewhere 'round 13Volts... not sure if your converter will like it... As Mackrackit says... "Always wear safety glasses while programming. "

[Fredrick]

Now i have a jumper from MCLR to the FTDI DTR pin via 100Ohms resistor and now the Microcode Loader works whitout any problems but the programming time is very slow about 10 sec for a 994 byts program, is there any way to speed that up?

But Microloader has a bug, if your computer does´t have any real serial ports you will not be available to change the COM port becouse the dropdownlist is locked and empty, however if you connect only one USB<-->Seriel cabel and then start the loader program the right com port will be selected and it work´s but the dropdownlist will still show "None" COM ports.

If you have a computer with a real serial port you will se both the real one and the virituel port in the dropdownlist.

And whitin MicroCode studio plus you will not be available to select the com port unless you change the device to a ICD compatibel PIC and then change the port and back to the PIC you are useing (in my case 18F2550.)

My Microcode Studio Version is 3.0.0.5