Mega48 PortB6 XTAL vs PortE XT1 external clock OSC

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The external clock is running fine but I don't understand something.

I have a Mega48 in the Stk500 running a 20MHZ external OSC. The clock is connected to PortE XT1. Typically I program tiny13's in the extended board I made using the 10 pin PortB connector. I originally thought I could just put the clock signal in portB6 on the portb 10 pin header but I see from the scope that this pin must be disconnected when the XTAL1 jumper is removed, is that correct? I get 20MHZ on the chip portb6 but on the 10 pin header I get nada.

Picture of setup attached.

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Look at the STK500 schematics to see where your clock signal is going, and grab it at an available spot and jumper.

Note: I don't think you will have good, reliable success in ISP of your remote AVR if you have another AVR mounted in one of the STK500 sockets.

Why wouldn't you program Tiny13s right on the STK500 instead of making another board?

Lee

You can put lipstick on a pig, but it is still a pig.

I've never met a pig I didn't like, as long as you have some salt and pepper.

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Quote:
Why wouldn't you program Tiny13s right on the STK500 instead of making another board?

I have a tendency to mash pins on small chips and large chips when taking them in and out of those chip holders on the stk500. Must have been all that bodybuilding I did over the years;). Actually my eyesight is so frikin bad I have a hard time poking the pins into the connectors, heck I have a hard time sometimes putting them into the ZIFF.

As you can see I have ZIF socket for the 28 pin socket on the stk500, I was unable to find an 8 pin ZIF that would fit in the stk500. I would like one though.

I have projects where I do alot of testing out of the programming area so making a programming change and popping the chip out and then back in to a portable breadboard is a common thing I do.

If there is a better way or a ZIFF socket that you have a part number for that will fit on the stk500 8 pin socket, I would buy it in a second.

Quote:

Note: I don't think you will have good, reliable success in ISP of your remote AVR if you have another AVR mounted in one of the STK500 sockets.

Absolutly, I never put two AVR's in at the same time.

Quote:

Look at the STK500 schematics to see where your clock signal is going, and grab it at an available spot and jumper.

Ahhh, thanks, I never realized those were in the document, that pretty much covers that.

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Given the layout of the STK500 sockets it would appear that any ZIF socket of the correct width could be placed into the 8-pin socket, with the remaining pins just hanging out toward the 20-pin socket.

For interference problems, mount a few plain 8-pin sockets into the permanent one on the STK500 to rasie the base of the ZIF over the jumper heades, etc.

Lee

You can put lipstick on a pig, but it is still a pig.

I've never met a pig I didn't like, as long as you have some salt and pepper.