=> [URGENT] - Need programmer circuit of PIC18f4550...

[chamith20xx]

Well Univercity is still technically a school.

The 18F4550 are better for C than the 16F series, they have the USB & I2C hardware and MicroC appears to support it.

Just hope your project isn't due anytime soon.

yes we are going to do the coding using C

 

[nurick]

Hello, I am intrigued with your discussion about PIC programmers, as I am lead to believe the same thing with Chamith (I am also a newbie PIC programmer, a freshman in college).

We are utilizing a 18f45j10 pic for our school project, and we are having trouble in coming up a circuit programmer for it. The programmer circuit must be made by us (we are required to), and by reading this thread, I have learned that several pic series may be programmed by the <b>same</b> programmer circuit <b>as long as</b> the software used is designated for that specific PIC.

So what happened is that we reused our old programmer circuit (for the 16f877 in our earlier projects) on the 18f45j10, but failed to make the PIC work. Any advice would be greatly appreciated. Thx in advance!

 

[eblc1388]

I have learned that several pic series may be programmed by the same programmer circuit as long as the software used is designated for that specific PIC.

Careful here. Several pic series may be programmed by the same programmer circuit as long as the programming software used includes device support for that specific PIC.

Which programming software are you using to control the programmer?

 

[nurick]

Thanks for pointing that out, eblc.

We are still looking for a suitable software programmer for the 18f45j10, since we have just known from this thread that programmer software supports only limited types of PICs. So far, we have tried using PICkit 2 (http://forum.microchip.com/printable.aspx?m=163347) but no luck. The problem may lie on the programer circuit itself as we are trying to troubleshoot the old circuit. Im also considering looking for a new programmer circuit schematic. Care to suggest something?


Thanks again for futher response.

 

[eblc1388]

So far, we have tried using PICkit 2 (http://forum.microchip.com/printable.aspx?m=163347) but no luck.

I don't understand. PICKit 2 v1.20 Released (May 16, 2006 8:00:06 AM) explicitly stated Support for 3V VDD PICs like 18F45J10.

Perhaps you would need to use the most update software version available here at Microchip download site. **broken link removed**

Edited: Also you might need to upgrade to the latest firmware V2.1 of the PICKit2, in the same download link above. Two upgrades operation needed, one is the firmware on the PICKit board and one is the PC control software.

 

[nurick]

@ L Chung: I dont think i can use the firmware since i dont have the PICKit2 board itself. I just used my old home-made circuit programmer. Could it be possible that the software requires a PICKit Board to actually work?

There's also the possibility that my programmer circuit is broken. Can you share a good programmer circuit schematic for a 40-pin PIC?

 

[eblc1388]

As I have said in previous post, the 18F45J10 is a 3.3V Vdd rated device. As such, any programmer must be of the type that can limit its signal/power levels between 0~3.3V.

3.3V capable PICs are there for a long time but usually they allow ICSP programming at 5V. The 18F45J10 don't.

I have not seen any schematic of DIY programmer stating support for 18F45J10, bear in mind that this type of PICs are new products and it will take a while before someone builds a DIY programmer for it.

Do you have other PIC choices other than this particular PIC?

 

[nurick]

I see. I get your drift now. So trying to create a home-made programmer circuit is futile since they dont operate at 3.3v or below. Thats why our circuit didn't work.

I have an alternative PIC for our project which is the surface-mounted 18F6722, I refuse to use this as soldering it to the board would be a pain. However, it might be our only choice ATM.