Microcode Studio Plus Loader?

[koossa]

I have upload the hex file (16F877_04.hex), but still gets the "Reset Required, please reset the target microcontroller in order to access to the bootloader process... ". error if I try to program it through my serial cable?

[Charles Linquis]

You need to insure that the serial port is working properly on both machines.

On my PC, I simply connect pins 2&3 together on the serial cable and hit a key. If the character echoes, then the PC end is working.

On the PIC side - Write a very simple program, such as:

DEFINE OSC 20 (or whatever it is)

DEFINE HSER_RCSTA 90H
DEFINE HSER_TXSTA 20H
DEFINE HSER_BAUD 9600
DEFINE HSER_CLROERR 1
DEFINE LOADER_USED 1

Dummy VAR BYTE

Begin:

HSEROUT ["Press Any Key "]
HSERIN [Dummy]
HSEROUT ["You Pressed ",Dummy,13,10]
GOTO Begin

END

The program above will prove that the PIC is sending and receiving characters - something it must do before any bootloader can work.

[koossa]

Hi Charles

Both sides are working perfectly, I am doing serial comms using HSEROUT and HSERIN.

Thx

[Charles Linquis]

Make sure Microcode Loader is set to use the correct serial port on your PC.

[koossa]

Yes, I have set that to Comm2.

[koossa]

I'm Using the PIC16F877 20/P with a 4MHz Crystal and then upload the 16F877_04.hex file.

Could my problem maybe be the "20/P"

Thx!

[keithdoxey]

I have upload the hex file (16F877_04.hex), but still gets the "Reset Required, please reset the target microcontroller in order to access to the bootloader process... ". error if I try to program it through my serial cable?

You say you are successfully doing serial comms already but this only requires TX and RX (as does the bootloadr for actual programming) but you need a way to restart the PIC so that it looks for the bootloader when it boots from a reset.

Do you have the DTR (Pin4) line connected to MCLR so that the bootloader can reset the PIC ?



IF not, you either need to do that, or have a reset button on your PCB that you can reset the PIC with (or power down the PIC).

I prefer the reset button method personally as previously when using the DTR line my program would reset when I opened the serial port on the PC.

Regards

[koossa]

Hi Keith

Thank you very much for your reply.
I have setup my PCB as described in this thread:
http://www.picbasic.co.uk/forum/show...ght=bootloader

But I did not build the reset button in, I have connect MCLR to the 10uF capacitor and the capacitor then goes to Pin9 on the MAX232.
Must I put the reset button in, as described on the thread above?
If so, when do I press the reset button?

Thx
Koossa

[keithdoxey]

Hi Keith

Thank you very much for your reply.
I have setup my PCB as described in this thread:
http://www.picbasic.co.uk/forum/show...ght=bootloader

But I did not build the reset button in, I have connect MCLR to the 10uF capacitor and the capacitor then goes to Pin9 on the MAX232.
Must I put the reset button in, as described on the thread above?
If so, when do I press the reset button?

Thx
Koossa

Hi Koossa,

I hadnt heard of the capacitor coupled version. It is exactly the same circuit except for the 10u capacitor instad of a 100R resistor. The difference being that instead of pulling MCLR permanently low it will only provide a short pulse. Maybe it is not pulling it low enough or for long enough.

The Reset button *shouldnt* be needed but having it gives the option of manually resetting your PIC at any time.

When the bootloader is displaying a message saying it is waiting for a reset, connect the MCLR pin to 0V momentarily and it should then reset the PIC and bootload the new program.

Just had a few more thoughts.....

1. When you programmed the bootloader into your PIC did you make sure that the MCLR pin was set as MCLR and not an IO pin ?

2. Is your MCLR pulled up with a resistor or have you tied it directly to +5V ?

3. Is Microcode loader set to "Auto" baud rate or is it fixed at the wrong speed?

4 Try the bootloader circuit with 100R instead of 10uF !

Other than that I cant think of anything else

Regards

[koossa]

Hi Keith

1. When you programmed the bootloader into your PIC did you make sure that the MCLR pin was set as MCLR and not an IO pin ?

How do I do that?

2. Is your MCLR pulled up with a resistor or have you tied it directly to +5V ?

With a Resistor.

3. Is Microcode loader set to "Auto" baud rate or is it fixed at the wrong speed?

Yes, to Auto

4 Try the bootloader circuit with 100R instead of 10uF !

Thx, I will try that.

[koossa]

When the bootloader is displaying a message saying it is waiting for a reset, connect the MCLR pin to 0V momentarily and it should then reset the PIC and bootload the new program.

I have connect the MCLR PINT TO 0V, but it still don't work.
I'm using the Max1672 switching regulator, and it has a soft on pin, so I must press the ON button on my keypad for the power to go through to my PIC.
I have done this and then momentarily connect MCLR to GND, but still no luck?

Any idea what else I can try?