Date   
Re: CDP1802 "Kit"

Magnus Kesselmark
 

Got a bunch of 1802’s from AliX. Cannot remember the price, but they were cheap. However not tested. Ordered a bunch (10) of SID circuits but sold them later. All were OK, but one or two of the 10 had a little low OP volume.
Also invested in two pairs 2SJ50/2SK135. Still have to check those up (for a future hybrid amp).
 
/M
 

Sent: Sunday, December 22, 2019 8:52 PM
Subject: Re: [cosmacelf] CDP1802 "Kit"
 
Does anyone purchase parts from Vendors on AliExpress?  In the last few years I've purchased '1802ACE chips (77 cents ea. @ qty 10), '1805ACE chips (free, pulls), '1806 chips (90 cents ea. @ qty 2), some 74HC573 chips (17.6 cents ea. @ qty 20), and a bunch of 128K HM628128 RAM ICs (average price 68 cents) and I've had good results.  Unfortunately, a reciprocal shipping agreement was cancelled in March so most items are a bit more expensive now but you can still find some bargains.

Happy Holidays.  Mike, K8LH

From: "Stuart Remphrey" <stu@...>
To: cosmacelf@groups.io
Sent: Sunday, December 22, 2019 11:41:31 AM
Subject: Re: [cosmacelf] CDP1802 "Kit"
 
Yup, their "Your price" is now higher at $12.95 -- but the "What you get" parts list still says $9.95 -- oops!
 
Still no 74HC373 included, though they sell them for 79c.
Or 74HC573 at 98c for "straighter" wiring if on bread/perf/strip-board?
 
Plus of course Lee's very generous PCB/ROM deal.
 
Hmm, also 74HC688 for 1.18; still could make up a reasonable parts-set for not much.
 

(Though for me that's 2 sets of international postage to Singapore, probably the most expensive "part"s!  -- maybe an excuse to by more, to better amortise shipping costs?!)
 

Re: CDP1802 "Kit"

 

Does anyone purchase parts from Vendors on AliExpress?  In the last few years I've purchased '1802ACE chips (77 cents ea. @ qty 10), '1805ACE chips (free, pulls), '1806 chips (90 cents ea. @ qty 2), some 74HC573 chips (17.6 cents ea. @ qty 20), and a bunch of 128K HM628128 RAM ICs (average price 68 cents) and I've had good results.  Unfortunately, a reciprocal shipping agreement was cancelled in March so most items are a bit more expensive now but you can still find some bargains.

Happy Holidays.  Mike, K8LH


From: "Stuart Remphrey" <stu@...>
To: cosmacelf@groups.io
Sent: Sunday, December 22, 2019 11:41:31 AM
Subject: Re: [cosmacelf] CDP1802 "Kit"

Yup, their "Your price" is now higher at $12.95 -- but the "What you get" parts list still says $9.95 -- oops!

Still no 74HC373 included, though they sell them for 79c.
Or 74HC573 at 98c for "straighter" wiring if on bread/perf/strip-board?

Plus of course Lee's very generous PCB/ROM deal.

Hmm, also 74HC688 for 1.18; still could make up a reasonable parts-set for not much.


(Though for me that's 2 sets of international postage to Singapore, probably the most expensive "part"s!  -- maybe an excuse to by more, to better amortise shipping costs?!)

Re: A video of my 1802 tester made from Arduino Mega

Hans Liss
 

This design is useful not only for testing the processors, but for actually learning about the 1802 and about microprocessors in general, so I've designed an Arduino Mega 2560 "shield" for this thing now. All the connections are there, and I added four buttons.

Any other ideas for useful things to add?

Hans

On 2019-12-21 15:04, jeff.birt wrote:

I’m glad it was helpful. Sorry for the bug on the DMA input. I never got around to actually wiring it up to the Arduino, so I did not find it 😊

There is a disassembly of all the test programs along with the Github project: https://github.com/Jeff-Birt/RCA1802_Tester

 

Jeff Birt

 

From: cosmacelf@groups.io <cosmacelf@groups.io> On Behalf Of Hans Liss
Sent: Saturday, December 21, 2019 3:32 AM
To: cosmacelf@groups.io
Subject: Re: [cosmacelf] A video of my 1802 tester made from Arduino Mega

 

Thanks Jeff for this brilliant test setup! I've now tested my own batch of Chinese 1802s - this was the only way I could do it at the moment. Turned out nine out of ten were in fact working!

One little detail that had me stumped for the longest time: When you initialize PORTK in setup(), you need to use "|" rather than "&", in order to set all the relevant pins high, otherwise the CPU may be stuck trying to do DMA from the start, like mine did.

I had lots of fun disassembling your EFx input test code to check what it was supposed to do, exactly. I also added a button and a randomization function for the EF pins, so that I can easily verify the functionality.

Best regards,

Hans

On 2019-11-25 01:47, jeff.birt wrote:

With a lot of help and encouragement form this mailing list I put together this Arduino Mega 2560 powered 1802 tester to test the lot of 10, 1802s I bought from a seller in China. While the initial simple set up was sufficient to find I had two bad chips it was fun to improve upon the test rig and I learned a lot about the 1802 in the process.

As luck would have it the serial command input quit responding during the video but has worked every time since. I left it in as that is what happens in real life, things always fail in a demo :)

https://youtu.be/XPwuwjtjXnk

Jeff Birt

 

Re: CDP1802 "Kit"

Stuart Remphrey
 

Yup, their "Your price" is now higher at $12.95 -- but the "What you get" parts list still says $9.95 -- oops!

Still no 74HC373 included, though they sell them for 79c.
Or 74HC573 at 98c for "straighter" wiring if on bread/perf/strip-board?

Plus of course Lee's very generous PCB/ROM deal.

Hmm, also 74HC688 for 1.18; still could make up a reasonable parts-set for not much.


(Though for me that's 2 sets of international postage to Singapore, probably the most expensive "part"s!  -- maybe an excuse to by more, to better amortise shipping costs?!)

Re: CDP1802 "Kit"

David Schultz
 

On 12/22/19 10:15 AM, ajparent1/kb1gmx wrote:
Yes they did.   I've not seen an invoice from them yet either.  The latter
is important as the order was pre price change.

They have been running a sale (12 days of Christmas) and that was the
sale price.


--
https://web.archive.org/web/20190214181851/http://home.earthlink.net/~david.schultz/
(Web pages available only at the Wayback Machine because Earthlink
terminated that service.)

Re: CDP1802 "Kit"

ajparent1/kb1gmx
 

Yes they did.   I've not seen an invoice from them yet either.  The latter
is important as the order was pre price change.

Re: CDP1802 "Kit"

 

I believe BG Micro just bumped the price for the CDP1802ACE processor by two bucks and the kit by three bucks...  

Re: A video of my 1802 tester made from Arduino Mega

jeff.birt
 

I’m glad it was helpful. Sorry for the bug on the DMA input. I never got around to actually wiring it up to the Arduino, so I did not find it 😊

There is a disassembly of all the test programs along with the Github project: https://github.com/Jeff-Birt/RCA1802_Tester

 

Jeff Birt

 

From: cosmacelf@groups.io <cosmacelf@groups.io> On Behalf Of Hans Liss
Sent: Saturday, December 21, 2019 3:32 AM
To: cosmacelf@groups.io
Subject: Re: [cosmacelf] A video of my 1802 tester made from Arduino Mega

 

Thanks Jeff for this brilliant test setup! I've now tested my own batch of Chinese 1802s - this was the only way I could do it at the moment. Turned out nine out of ten were in fact working!

One little detail that had me stumped for the longest time: When you initialize PORTK in setup(), you need to use "|" rather than "&", in order to set all the relevant pins high, otherwise the CPU may be stuck trying to do DMA from the start, like mine did.

I had lots of fun disassembling your EFx input test code to check what it was supposed to do, exactly. I also added a button and a randomization function for the EF pins, so that I can easily verify the functionality.

Best regards,

Hans

On 2019-11-25 01:47, jeff.birt wrote:

With a lot of help and encouragement form this mailing list I put together this Arduino Mega 2560 powered 1802 tester to test the lot of 10, 1802s I bought from a seller in China. While the initial simple set up was sufficient to find I had two bad chips it was fun to improve upon the test rig and I learned a lot about the 1802 in the process.

As luck would have it the serial command input quit responding during the video but has worked every time since. I left it in as that is what happens in real life, things always fail in a demo :)

https://youtu.be/XPwuwjtjXnk

Jeff Birt

 

Re: A video of my 1802 tester made from Arduino Mega

Hans Liss
 

Thanks Jeff for this brilliant test setup! I've now tested my own batch of Chinese 1802s - this was the only way I could do it at the moment. Turned out nine out of ten were in fact working!

One little detail that had me stumped for the longest time: When you initialize PORTK in setup(), you need to use "|" rather than "&", in order to set all the relevant pins high, otherwise the CPU may be stuck trying to do DMA from the start, like mine did.

I had lots of fun disassembling your EFx input test code to check what it was supposed to do, exactly. I also added a button and a randomization function for the EF pins, so that I can easily verify the functionality.

Best regards,

Hans

On 2019-11-25 01:47, jeff.birt wrote:

With a lot of help and encouragement form this mailing list I put together this Arduino Mega 2560 powered 1802 tester to test the lot of 10, 1802s I bought from a seller in China. While the initial simple set up was sufficient to find I had two bad chips it was fun to improve upon the test rig and I learned a lot about the 1802 in the process.

As luck would have it the serial command input quit responding during the video but has worked every time since. I left it in as that is what happens in real life, things always fail in a demo :)

https://youtu.be/XPwuwjtjXnk

Jeff Birt

 

Re: CDP1802 "Kit"

ajparent1/kb1gmx
 

Lee,

Order is in for two of the special 2. 

Allison

Re: CDP1802 "Kit"

Peter Renaud
 

Hi,
That’s a great deal! Where do I sign up? I already have the parts from my Cosmac Elf build and I have a programmer. I was thinking of also getting the BGmicro kit but shipping to Canada was more than half the cost.
Thanks


From: cosmacelf@groups.io <cosmacelf@groups.io> on behalf of Lee Hart <leeahart@...>
Sent: Friday, December 20, 2019 1:26:56 AM
To: cosmacelf@groups.io <cosmacelf@groups.io>
Subject: Re: [cosmacelf] CDP1802 "Kit"
 
Lee Hart wrote:
> I'll put some Paypal "buy now" buttons on my web page at
> <www.sunrise-ev.com/1802.htm> to make these options easier to order. Look
> for them tomorrow!

OK; I made a couple new Paypal buttons at
<http://www.sunrise-ev.com/1802.htm>. To keep from getting buried by too
many options, I just provided two:

*SPECIAL #1* is $8.00 for just the 1802MC CPU board.

*SPECIAL #2* is $10.00 for the 1802MC CPU board, a 32K EPROM programmed
with the MCSMP20 monitor and RCA's BASIC3, and a 32K RAM.

The EPROM and RAM supplied with the BGMicro kit will work in the 1802MC;
but not at the same time. Download the manual on the same web page for
details. :-)

Happy Holidays,
Lee Hart
--
Obsolete (Ob-so-LETE). Adjective. 1. Something that is simple,
reliable, straightforward, readily available, easy to use, and
affordable. 2. Not what the salesman wants you to buy.
--
Lee Hart, 814 8th Ave N, Sartell MN 56377, www.sunrise-ev.com



Re: CDP1802 "Kit"

Lee Hart
 

Lee Hart wrote:
I'll put some Paypal "buy now" buttons on my web page at
<www.sunrise-ev.com/1802.htm> to make these options easier to order. Look
for them tomorrow!
OK; I made a couple new Paypal buttons at <http://www.sunrise-ev.com/1802.htm>. To keep from getting buried by too many options, I just provided two:

*SPECIAL #1* is $8.00 for just the 1802MC CPU board.

*SPECIAL #2* is $10.00 for the 1802MC CPU board, a 32K EPROM programmed with the MCSMP20 monitor and RCA's BASIC3, and a 32K RAM.

The EPROM and RAM supplied with the BGMicro kit will work in the 1802MC; but not at the same time. Download the manual on the same web page for details. :-)

Happy Holidays,
Lee Hart
--
Obsolete (Ob-so-LETE). Adjective. 1. Something that is simple,
reliable, straightforward, readily available, easy to use, and
affordable. 2. Not what the salesman wants you to buy.
--
Lee Hart, 814 8th Ave N, Sartell MN 56377, www.sunrise-ev.com

Re: CDP1802 "Kit"

Lee Hart
 

Lee Hart wrote:

Here's a Christmas "card" for all you Elves. Order one of these 1802
kits from BGMicro, and I'll provide an 1802MC CPU board to use them
for $8 (plus postage to wherever you live).
...
There are a few other small parts you'll need; a few resistors and
capacitors, a 74HC373 address latch, etc. You can also add a few more
chips to provide an input and output ports.

Merry Christmas!
Lee Hart
Thanks for the orders! This will keep Santa's elves busy. :-)

Some additions to my hastily-posted offer:

1. Send orders directly to me at <leeahart@...> to avoid clutter on the cosmacelf list.

2. I didn't notice that the BGMicro #9Z1510 kit comes with a 0.6" wide RAM chip (MCM6064P12). The 1802MC PCB is set up for a 0.6" wide EPROM (like the 2732) and a 0.3" wide RAM (like the CY7C199).

BGMicro has a Toshiba TC5588P-20 0.3" wide 8K RAM (their #ICSTC5588P) for $1.39. I haven't tried it yet, but it should drop right in to the 1802MC board. Either order one with your kit, or ask if they can substitute it for the MCM6064P12.

3. If you've already ordered your BGMicro kit, I can provide the CY7C199 32k RAM for $2 each. Bonus; it increases your RAM to 32k. :-)

4. Both Tiny BASIC and the IDIOT monitor fit in one 4K EPROM.

5. Or, if you're getting the EPROM from me, I can also provide a 32k EPROM with Chuck Yakym's MCSMP20 monitor and BASIC3 for the same price $2).

I'll put some Paypal "buy now" buttons on my web page at <www.sunrise-ev.com/1802.htm to make these options easier to order. Look for them tomorrow!

Happy ho-ho-holidays!
Lee Hart


--
Obsolete (Ob-so-LETE). Adjective. 1. Something that is simple,
reliable, straightforward, readily available, easy to use, and
affordable. 2. Not what the salesman wants you to buy.
--
Lee Hart, 814 8th Ave N, Sartell MN 56377, www.sunrise-ev.com

Re: CDP1802 "Kit"

 

Slightly off-topic but I was thinkin'...  Wouldn't it be nice to take advantage of the extra memory on those 128K RAM chips.  An 'untested' concept for mapping 16K banks in and out of the 64K address space is attached.

Cheerful regards, Mike


From: "Bob Armstrong" <bob@...>
To: cosmacelf@groups.io
Sent: Thursday, December 19, 2019 10:33:55 AM
Subject: Re: [cosmacelf] CDP1802 "Kit"

... selecting ROM with A15 on /CE (pin 18) and selecting RAM with A15 on active high E2
  That's what I had in mind.  As for I/O, you could use one of those TTL level USB to serial adapters and connect it directly to Q and some EFx pin.  With the sole addition of the address latch, you should have enough here to run Tiny BASIC.
 

Re: CDP1802 "Kit"

Lee Hart
 

Bob Armstrong wrote:
... selecting ROM with A15 on /CE (pin 18) and selecting RAM with
A15 on active high E2
That's what I had in mind. As for I/O, you could use one of those
TTL level USB to serial adapters and connect it directly to Q and some
EFx pin. With the sole addition of the address latch, you should have
enough here to run Tiny BASIC.
Good point, Bob.

Here's a Christmas "card" for all you Elves. Order one of these 1802 kits from BGMicro, and I'll provide an 1802MC CPU board to use them for $8 (plus postage to wherever you live).

(Obviously, you don't need their kit, if you already have the parts in your junk box.)

If you have an EPROM programmer for the 2732 they supply, I have the code for Tiny BASIC and the IDIOT monitor on my website. Program this into the EPROM, and you're in business!

If you don't have a programmer, I can supply a programmed EPROM for another $2.

There are a few other small parts you'll need; a few resistors and capacitors, a 74HC373 address latch, etc. You can also add a few more chips to provide an input and output ports.

Merry Christmas!
Lee Hart

--
Obsolete (Ob-so-LETE). Adjective. 1. Something that is simple,
reliable, straightforward, readily available, easy to use, and
affordable. 2. Not what the salesman wants you to buy.
--
Lee Hart, 814 8th Ave N, Sartell MN 56377, www.sunrise-ev.com

Re: CDP1802 "Kit"

 

... selecting ROM with A15 on /CE (pin 18) and selecting RAM with A15 on active high E2
  That's what I had in mind.  As for I/O, you could use one of those TTL level USB to serial adapters and connect it directly to Q and some EFx pin.  With the sole addition of the address latch, you should have enough here to run Tiny BASIC.
 

Re: CDP1802 "Kit"

 

Perhaps something like this (attached) for RAM expansion (128K RAM chips are cheap) and then do something similar for the ROM (EEPROM)?  Still need some I/O...



From: "Lee Hart" <leeahart@...>
To: cosmacelf@groups.io
Sent: Wednesday, December 18, 2019 11:22:17 PM
Subject: Re: [cosmacelf] CDP1802 "Kit"

Mike McLaren, K8LH wrote:
> Would there be any problems latching all eight upper address bits by
> adding a single '373 or '573 and selecting ROM with A15 on /CE (pin 18)
> and selecting RAM with A15 on active high E2 (pin 26) with active low
> /E1 (pin 20) grounded?  You'd have eight 4K ROM images spanning
> $0000..$7FFF and four 8K RAM images spanning $8000..$FFFF.

I didn't look up the specs for that 8K RAM. If it has an active-high
chip select, your scheme should work! It provides more memory than my
minimal scheme. :-)

If you're going to make a board, you might as well lay it out with
jumper options to also support up to a 32k EPROM, and 128k RAM. There
are 128k RAMs that also have an active-high chip select pin. You could
only use 32k of that RAM, but you'd have a 4-chip system with 64k of
memory and a bit-banger serial port.

Lee

--
ICEs have the same problem as lightbulbs. Why innovate and make
better ones when the current ones burn out often enough to keep
you in business? -- Hunter Cressall
--
Lee Hart, 814 8th Ave N, Sartell MN 56377, www.sunrise-ev.com




Re: CDP1802 "Kit"

Lee Hart
 

Mike McLaren, K8LH wrote:
Would there be any problems latching all eight upper address bits by
adding a single '373 or '573 and selecting ROM with A15 on /CE (pin 18)
and selecting RAM with A15 on active high E2 (pin 26) with active low
/E1 (pin 20) grounded? You'd have eight 4K ROM images spanning
$0000..$7FFF and four 8K RAM images spanning $8000..$FFFF.
I didn't look up the specs for that 8K RAM. If it has an active-high chip select, your scheme should work! It provides more memory than my minimal scheme. :-)

If you're going to make a board, you might as well lay it out with jumper options to also support up to a 32k EPROM, and 128k RAM. There are 128k RAMs that also have an active-high chip select pin. You could only use 32k of that RAM, but you'd have a 4-chip system with 64k of memory and a bit-banger serial port.

Lee

--
ICEs have the same problem as lightbulbs. Why innovate and make
better ones when the current ones burn out often enough to keep
you in business? -- Hunter Cressall
--
Lee Hart, 814 8th Ave N, Sartell MN 56377, www.sunrise-ev.com

Re: CDP1802 "Kit"

 

It's just an alternative to Lee's "simplest circuit I can think of" which provides at least the same, probably more, capability compared to the 4042 suggestion.  Of course you still need to add I/O.

Why do you think the suggested circuit would hinder expansion?  Layout your board with a 32-pin RAM socket and plug in the 8K RAM or a 64K RAM and the same decoding scheme (active lo A15 = ROM, active hi A15 = RAM) will map 32K of RAM into the address space at $8000..$FFFF with the 64K RAM chip installed.  64K and 128K RAM chips are relatively inexpensive.  You can do something similar to expand the ROM.  

Mike


From: "ajparent1/kb1gmx" <kb1gmx@...>
To: cosmacelf@groups.io
Sent: Wednesday, December 18, 2019 10:11:36 PM
Subject: Re: [cosmacelf] CDP1802 "Kit"

Mike,
That works but only if further expansion is not needed.
No one says you must fully decode addresses.

Re: CDP1802 "Kit"

ajparent1/kb1gmx
 

Mike,
That works but only if further expansion is not needed.
No one says you must fully decode addresses.