T TKS New Member Mar 1, 2006 #1 Hi, I was wondering what if we connect the 16F819. CLKOUT pin to the clock source of a wafer card. The 16F819 will then be programmed to use the internal Clock Source. I'm searching for an way to give the Goldwafer card an clock source and have no idea how to generate one. The problem i have is that if hook it up to the 20Mhz osc it stops the pic connected to it from working. Sowww what are the ideas??? Regards, TKs
Hi, I was wondering what if we connect the 16F819. CLKOUT pin to the clock source of a wafer card. The 16F819 will then be programmed to use the internal Clock Source. I'm searching for an way to give the Goldwafer card an clock source and have no idea how to generate one. The problem i have is that if hook it up to the 20Mhz osc it stops the pic connected to it from working. Sowww what are the ideas??? Regards, TKs
Nigel Goodwin Super Moderator Most Helpful Member Mar 1, 2006 #2 Use a buffer from the oscillator to the card!.
T TKS New Member Mar 1, 2006 #3 how to build the buffer?? cant i just hookup the osc to the card?? what is needed?? tks
Nigel Goodwin Super Moderator Most Helpful Member Mar 1, 2006 #4 Re: how to build the buffer?? TKS said: cant i just hookup the osc to the card?? what is needed?? tks Click to expand... As you've already found out, often the extra load will stop the clock (particularly at 20MHz), either use a transistor buffer or a spare CMOS logic gate.
Re: how to build the buffer?? TKS said: cant i just hookup the osc to the card?? what is needed?? tks Click to expand... As you've already found out, often the extra load will stop the clock (particularly at 20MHz), either use a transistor buffer or a spare CMOS logic gate.
T TKS New Member Mar 1, 2006 #5 Ok, Sow in fact i just need to run the clock ouput from the chip to the base from an BC374 (the commen used one) and then i just put an 5volt on thecollector of the transitor and the emitter to the clock signal. Also i put 2 10K's to the base to ground?? and the clock line to ground?? (emitter side).. Is this right?? Tks p.s. i also have an HC7400 but i have no idea... if this needs any extra components..
Ok, Sow in fact i just need to run the clock ouput from the chip to the base from an BC374 (the commen used one) and then i just put an 5volt on thecollector of the transitor and the emitter to the clock signal. Also i put 2 10K's to the base to ground?? and the clock line to ground?? (emitter side).. Is this right?? Tks p.s. i also have an HC7400 but i have no idea... if this needs any extra components..
Nigel Goodwin Super Moderator Most Helpful Member Mar 1, 2006 #6 I've never had occasion to do it, but there's an application note somewhere at MicroChip about it!.