[Coco] Kip's Single Board Computer
Dave Philipsen
dave at davebiz.com
Sat Sep 19 02:08:34 EDT 2015
Correction: I shouldn't say the 68HC11 can't do relocatable code it's
just not as versatile or as feasible as it is with the 6809.
Dave
On 9/19/2015 12:08 AM, Dave Philipsen wrote:
> Kip, would you rather build one from scratch or just get one already
> built? I have a number of them already built that I could send out.
> I'll try to write up a little documentation for it. I also have an
> assembler and a monitor for it. For some things it can be faster than
> a 6809 because of the 4MHz speed but of course it won't do relocatable
> code. If you're familiar with 6809 assembler code this will be a
> cinch to pick up. Some mnemonics are a little different but more ways
> similar than not.
>
> Dave
>
>
> P.S. I got the Moxham board in the mail yesterday and ordered the FPGA
> dev board for it. Looks pretty interesting!
>
>
> On 2015-09-18 23:47, Kip Koon wrote:
>> Hi Dave,
>> I would very much like to experiment with your HC11 PCB. It looks
>> very interesting. I'm currently reading a book called Microcontroller
>> Technology - 68HC11 & 68HC12. It would be interesting to play with
>> this board as I learn the 68HC11. I have several HC11F1 chips on hand
>> I could use. Please let me know everything I need to get this PCB
>> going. Thanks a bunch in advance!
>>
>> Kip Koon
>> computerdoc at sc.rr.com
>> http://www.cocopedia.com/wiki/index.php/Kip_Koon
>>
>>
>>> -----Original Message-----
>>> From: Coco [mailto:coco-bounces at maltedmedia.com] On Behalf Of Dave
>>> Philipsen
>>> Sent: Tuesday, September 15, 2015 2:00 PM
>>> To: CoCoList for Color Computer Enthusiasts
>>> Subject: Re: [Coco] Kip's Single Board Computer
>>>
>>> Yep, it probably will. The beauty of the 'reset' chip is that it
>>> continuously monitors VCC for an out-of-range value and will put the
>>> CPU
>>> back in reset if it finds that. A lot of times what causes a CPU to
>>> 'lock up' is some dirty supply voltage that cause the something
>>> abnormal to show up on the data/address lines and then the CPU takes
>>> a hike to la-la land. This chip is like a power supply watchdog.
>>> It also conditions a reset button input because, as you probably
>>> know, mechanical switches can be noisy/bouncy.
>>>
>>> Here's a photo of a more recent revision of the board that I did
>>> with onboard 5v regulator and a power supply barrel connector. The
>>> 'HC11 runs at 4 MHz bus speed, has full 16-bit external address bus,
>>> buffered data lines, some decoded chip selects, internal 1K SRAM,
>>> internal 512-byte EEPROM, serial port, SPI port. The board has all
>>> of the signals brought out to expansion connectors, the reset chip,
>>> a 16 MHz oscillator, RS232 port, power LED. socket for RTC and
>>> external EEPROM,
>>> 27C256 EPROM socket, etc. If anyone's interested in playing around
>>> with one or building it from scratch I could make up some
>>> documentation for it along with a basic monitor in EPROM. I think I
>>> still have quite a few bare boards floating around that I would sell
>>> for cheap. And, it's a tried and tested design. As I said, I
>>> produce somewhere in the neighborhood of 1,000-1,500 of these and
>>> they're
>>> all still running now.
>>>
>>> http://www.davebiz.com/HC11-new.jpg
>>>
>>> Dave Philipsen
>>>
>>>
>>>
>>> On , John W. Linville wrote:
>>> > Well, that seems fine. But I think a simple capacitor will do the
>>> > job... :-)
>>> >
>>> > John
>>> >
>>> > On Tue, Sep 15, 2015 at 12:34:59PM -0500, Dave Philipsen wrote:
>>> >> So I just sent Jim an offer to send a couple of DS1233-10 chips.
>>> The
>>> >> chip basically holds a CPU in reset for 350ms after the power supply
>>> >> comes up and is stable. I have used probably 1,500-2,000 of these
>>> >> over the years in a little 68HC11 board I designed about 20 years
>>> >> ago:
>>> >>
>>> >> http://www.davebiz.com/HC11.jpg
>>> >>
>>> >> You can see the DS1233-10 in the upper left corner of the board next
>>> >> to the oscillator chip.
>>> >>
>>> >> Dave
>>> >>
>>> >>
>>> >> On , John W. Linville wrote:
>>> >> >On Tue, Sep 15, 2015 at 12:06:04PM -0500, RETRO Innovations wrote:
>>> >> >>On 9/15/2015 11:49 AM, John W. Linville wrote:
>>> >> >>>On Tue, Sep 15, 2015 at 12:15:15PM -0400, RETRO Innovations
>>> wrote:
>>> >> >>>> The new board, as it were (it's getting less new by the
>>> month) is Kip's
>>> >> >>>> take on Searle's 6 IC 6809. His is 8, and offers some
>>> interesting
>>> >> >>>> enhancement options.
>>> >> >>>>
>>> >> >>>> But, when I try to bring the board up, I'm struggling:
>>> >> >>>>
>>> >> >>>> * there is no signal on Q or E.
>>> >> >>>> * Nothing of interest on the crystal pins (though my
>>> Tek could be
>>> >> >>>> interfering with the feedback).
>>> >> >>>> * I took the CPU off the board, breadboarded with HALT
>>> and RESET
>>> >> >>>> high, crystal and caps installed, and still no Q or
>>> E. I tried a
>>> >> >>>> known working 6809 from my SuperPET, and nothing.
>>> >> >>>>
>>> >> >>>> I'm new to 6809/6309, so I am not sure where to start. I
>>> am sure once
>>> >> >>>> I get the CPU running, the rest will be quick work, but
>>> the fact that I
>>> >> >>>> can't seem to get a 6809 by itself to generate Q and E
>>> bothers me and
>>> >> >>>> lowers my confidence that the board is ready to be debugged.
>>> >> >>>>
>>> >> >>>> Kip, send the man a board. I'll buy it for him.
>>> >> >>>>
>>> >> >>>> Jim
>>> >> >>>I'm fairly certain that the clock problem is caused by the
>>> lack of
>>> >> >>>RC circuit on the RESET^ line, as I described in my earlier
>>> >> >>>note...do I get a board too? :-)
>>> >> >>>
>>> >> >>>John
>>> >> >>Happy to buy you one. My time is precious, and saving 2-3
>>> hours on
>>> >> >>the bench is worth quite a bit at this stage in my life.
>>> >> >>
>>> >> >>So, for the 6809 noob, is there a data sheet page I should
>>> >> >>reference for the correct cap/resistor values?
>>> >> >
>>> >> >So, the RESET^ reference on page 6 points to Figure 7 (which is on
>>> >> >page 8). There it refers to the initial low time as "tRC".
>>> >> >
>>> >> >Near the bottom of the chart in Figure 1 (on page 3) it shows a
>>> >> >maximum value for tRC as 100mS. Oddly, no minimum is listed.
>>> >> >
>>> >> >Referring to the Simon6809 schematic, it looks like he is using
>>> an R
>>> >> >of 10Kohm and a C of 10uF. That should put you right at that 100mS
>>> >> >"maximum", but it works fine.
>>> >> >
>>> >> >Anyway, I would suggest something approaching 100mS. Since Kip
>>> >> >seems to have a 2.2Kohm pull-up on RESET^, maybe a 47uF capacitor
>>> >> >from there to ground? Of course, that ignores the R10 and LED
>>> >> >path...you may have to try some different cap values if that
>>> doesn't work...
>>> >> >
>>> >> >>I remember the reset controller from my 68hc11 days. Man,
>>> Motorola
>>> >> >>was picky on reset.
>>> >> >
>>> >> >:-)
>>> >> >
>>> >> >John
>>> >> >--
>>> >> >John W. Linville Someday the world will need a hero, and you
>>> >> >linville at tuxdriver.com might be all we have. Be ready.
>>> >>
>>> >> --
>>> >> Coco mailing list
>>> >> Coco at maltedmedia.com
>>> >> https://pairlist5.pair.net/mailman/listinfo/coco
>>> >
>>> > --
>>> > John W. Linville Someday the world will need a hero, and you
>>> > linville at tuxdriver.com might be all we have. Be ready.
>>>
>>> --
>>> Coco mailing list
>>> Coco at maltedmedia.com
>>> https://pairlist5.pair.net/mailman/listinfo/coco
>
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