As I understand it, yes, you want the crystal or resonator as close to the SX as possible for EMI/RFI considerations.....
I have had a ceramic resonator as far as one inch away and did not see any side affects as far as program operation. I have no idea what that did to EMI/RFI levels.
I belive you can put the jumpers in and the crystal as close to the SX as possible without a problem, but I would not build 10's of boards that way until confirming with a prototype.
For my boards, I use a four position inline socket, with three positions set up to take a through hole resonator, the fourth to supply power to the key. To program I remove the resonator and plug the SXkey into the four position socket, using an adapter to make the pinout correct for the key. Works fine, even with several inches of wire between the board and the SXkey. I've even used a cable attached to the adapter to supply +5V from my laptop's mouse port to allow reprogramming of modules in the field.
when you just want to do ISP, the clock jumper is not actually required, as resonators and crystals usually can stand the 12V programming voltage. On the other hand, when you want to do in system debugging, it is necessary to disconnect the resonator/crystal somehow, otherwise the SX-Key would not work.
XGen
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I have had a ceramic resonator as far as one inch away and did not see any side affects as far as program operation. I have no idea what that did to EMI/RFI levels.
I belive you can put the jumpers in and the crystal as close to the SX as possible without a problem, but I would not build 10's of boards that way until confirming with a prototype.
Ken
when you just want to do ISP, the clock jumper is not actually required, as resonators and crystals usually can stand the 12V programming voltage. On the other hand, when you want to do in system debugging, it is necessary to disconnect the resonator/crystal somehow, otherwise the SX-Key would not work.
Greetings,
G