Re: ISP issues

On Saturday 28 Feb 2004 8:34 am, Jason Kyle wrote:
> At 00:33 28/02/2004 -0500, Brian Dean wrote:
> >On Fri, Feb 27, 2004 at 11:10:44PM -0500, David Willmore wrote:
> > > I'm trying to program a large number of 90S2313s, so
> > > I knocked up a ZIF socket to a 6 pin header and put
> > > in a little power supply.
> > >
> > > I tested the wiring and it seems to be right, but
> > > neither of the ISP capable programmers I have--
> > > STK500 and an AVRisp--seems to want to touch it.
> > > They read back the target voltage just fine, but
> > > fail to go into program mode.
> > >
> > > Is there anything special that needs to be in the
> > > target for an ISP programmer to work?  Pullup
> > > resistors or anything?
> > >
> > > I used a VOM to verify that my fixture matches
> > > the connections in the STK500 on the Vcc, GND,
> > > RESET, SCK, MISO, and MOSI pins.  Do I need anything
> > > else?
> >
> >Clock source - crystal, resonator, external clock or something.  I
> >don't think the AT90S2313's have a built-in oscillator.
>
> You're right Brian.  These old devices need a clock source in order
> to be programmed.  David, solder a ceramic resonator or crysal onto
> that socket and all will be well.
and a couple of loading capacitors, or a resonator with them built-in.

...next week - how to suck eggs.
-- 
Richard Urwin