8-bit MicrocontrollersのトピックRe: HC08AP32A

HC08AP32A

byteybird — Sat, 15 Apr 2006 02:39:15 GMT

I'm using the A version of this part because it accepts a crystal from 1 to 8Mhz, whereasa the "non A" accepts a 32KHz crystal. I'm having a problem where the 8 MHz crystal is not oscillationg (I'm using 20 pF on each leg to ground). I build 6-boards. the first two I put together (using samples from freescale) work. The other 4-boards (micros were purchased) only 1 boards is oscillationg. The other 3, the circuit is not working. I am not using the phase lock loop. I also tried a 4 and an 8 Mhz resonator.

I replaced the micro on one of the boards and still the crystal is not oscillating. The boards work find if I used an external oscillator. This should be the simplest part of the total design. Could the parts be mismarked and I actually received the "Non A" device.

Any suggestion would be greatly appreciated.

Re: HC08AP32A

peg — Sat, 15 Apr 2006 08:22:00 GMT

Hi byteybird,

I presume you have 1 10Meg or so parallel resistor and NO series resistor (as you might with a 32kHz xtal).

Have you tried a "good" xtal in a "bad" board. I have seen quite a few "dud" crystals.

BR Peg

Re: HC08AP32A

byteybird1 — Sat, 15 Apr 2006 10:11:34 GMT

I currently have the board set-up with an 8-Mhz Ceramic Resonator (3-lead with built in 20 pF by-pass capactors) and 10M bypass resistor. I have tried all combination, 1Mhz Resistor, 4Mhz Resonator, 8Mhz crystal. I even have an FAE from Freescale create a small program based upon my schematic just to blink a led design with an 8Mhz crystal and no-phase loop loop. Same results. This board works fine with an external oscillator.