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Cromemco dazzler replica project

here are some test demos i wrote in MBASIC 5.21 a few years ago for the dazzler.

these implement double buffering.


 
Can anyone who has the GRAPHZ80.REL library link it with a noddy program and upload the resulting executable image for me to disassemble please.

Cheers in advance,

Dave
 
I've finished putting together a BOM for both Dazzler boards..
docs.google.com

Dazzler BOM

Sheet1 Location,Quantity,Source,Cost,Qty Ordered ICs 7805,IC1,38,2,<a href="https://www.ebay.com/itm/382100890477">https://www.ebay.com/itm/382100890477</a>,$1.00,2 7410,IC2,16,17,18,4,<a href="https://www.ebay.com/itm/296155775499">https://www.ebay.com/itm/296155775499</a>,$7.84,10 7473,IC3,10,...
docs.google.com docs.google.com

For the eBay parts I tried to group as many as I could from the same seller to reduce shipping costs. Though I have no idea how long these links will be valid, I'm pretty sure a few of the items were the last ones in stock.

Some of the parts are in a Mouser project which is linked to from the BOM, also linking to it here:

In the BOM sheet, there is an "extra sets/costs" column - this is because I may have had to order more parts than I need to build a single board set. If anyone ends up wanting to build one of these I can sell the spare parts I have at cost+shipping. I intend to test every 74 logic chip as they come in. Unfortunately ordering all vintage/ceramic parts would be prohibitively expensive. Would be nice, but I still need to be able to feed my family. :)
 
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nullvalue said:
I've finished putting together a BOM for both Dazzler boards..
docs.google.com

Dazzler BOM

Sheet1 Location,Quantity,Source,Cost,Qty Ordered ICs 7805,IC1,38,2,<a href="https://www.ebay.com/itm/382100890477">https://www.ebay.com/itm/382100890477</a>,$1.00,2 7410,IC2,16,17,18,4,<a href="https://www.ebay.com/itm/296155775499">https://www.ebay.com/itm/296155775499</a>,$7.84,10 7473,IC3,10,...
docs.google.com docs.google.com

For the eBay parts I tried to group as many as I could from the same seller to reduce shipping costs. Though I have no idea how long these links will be valid, I'm pretty sure a few of the items were the last ones in stock.

Some of the parts are in a Mouser project which is linked to from the BOM, also linking to it here:

In the BOM sheet, there is an "extra sets/costs" column - this is because I may have had to order more parts than I need to build a single board set. If anyone ends up wanting to build one of these I can sell the spare parts I have at cost+shipping. I intend to test every 74 logic chip as they come in. Unfortunately ordering all vintage/ceramic parts would be prohibitively expensive. Would be nice, but I still need to be able to feed my family. :)
Click to expand...
On the small details side of things, it pays to find the original large sized crystal, the same type of round ceramic tuning capacitor with the correct footprint the pcb holes are larger to accommodate this on my board(or should be on other boards) and vertical mount preset pots where the adjustment screw slot faces directly to the rear. It is a better arrangement for ease of adjustment when the board is plugged in beside others on the SOL-20 for example. As I recall I also slightly moved the position of the video output pins to clear the plastic card slides in the SOL-20.
 
Hugo Holden said:
On the small details side of things, it pays to find the original large sized crystal, the same type of round ceramic tuning capacitor with the correct footprint the pcb holes are larger to accommodate this on my board(or should be on other boards) and vertical mount preset pots where the adjustment screw slot faces directly to the rear. It is a better arrangement for ease of adjustment when the board is plugged in beside others on the SOL-20 for example. As I recall I also slightly moved the position of the video output pins to clear the plastic card slides in the SOL-20.
Click to expand...

Hey, thanks for your suggestions. For the crystal, this is the one I ordered: https://www.ebay.com/itm/324326440720 - i found the link to that in this thread as one that *should* work. It is in an HC-6 case - what case/size was the original? The tuning caps I also ordered from a link in this thread: https://www.ebay.com/itm/252832430337 - could you verify these are the right parts?

As far as the pots, this is what I had chosen: https://www.mouser.com/ProductDetail/652-3386C-1-501LF, are you saying something like this might be better? https://www.mouser.com/ProductDetail/594-63P501 Would you mind providing the PN you used?
 
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nullvalue said:
Hey, thanks for your suggestions. For the crystal, this is the one I ordered: https://www.ebay.com/itm/324326440720 - i found the link to that in this thread as one that *should* work. It is in an HC-6 case - what case/size was the original? The tuning caps I also ordered from a link in this thread: https://www.ebay.com/itm/252832430337 - could you verify these are the right parts?

As far as the pots, this is what I had chosen: https://www.mouser.com/ProductDetail/652-3386C-1-501LF, are you saying something like this might be better? https://www.mouser.com/ProductDetail/594-63P501 Would you mind providing the PN you used?
Click to expand...
That crystal looks good and the ceramic cap too. With the pots, the second link ones are better, you just need to check on your particular PCB the footprint to decide which variant fits.

I used a crystal that already had an earth wire soldered to its body already, simply removed that and soldered it to the wire link that ran on top of the Xtal to hold it down. If your crystal body has never been soldered to before I would not recommend doing that, and simply put some thin insulation over the wire hoop that holds the crystal down instead.
 
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wperko said:
Hi,

Yeah, I jumped on six of the "TMS3417JDC RARE VINTAGE TEXAS PMOS DYNAMIC SHIFT REGISTER CERAMIC ICs" as soon as I saw the eBay listing. As a poor low-income senior I'm hoping to eventually build one DAZZLER board set for my own computer, then trade off the extra TMS3417JDC chips ...

All the other places I tried for "quotes" did not have the TMS3417JDC available, so yeah, that maybe the last of them on the planet. Nice that they're NOS!


.
Click to expand...
Just arrived

1708240703931.png

1708240774017.png
 
nullvalue said:
Hey, thanks for your suggestions. For the crystal, this is the one I ordered: https://www.ebay.com/itm/324326440720 - i found the link to that in this thread as one that *should* work. It is in an HC-6 case - what case/size was the original? The tuning caps I also ordered from a link in this thread: https://www.ebay.com/itm/252832430337 - could you verify these are the right parts?

As far as the pots, this is what I had chosen: https://www.mouser.com/ProductDetail/652-3386C-1-501LF, are you saying something like this might be better? https://www.mouser.com/ProductDetail/594-63P501 Would you mind providing the PN you used?
Click to expand...
@nullvalue probably you bought the last items for the crystal, stock seems empty right now :)

Just in case you prefer a pot closer the the original, DigiKey seems to provide the suitable parts, see https://www.digikey.com/en/products/detail/tt-electronics-bi/91AR500LF/3587322
 
Ansgar Kueckes said:
Just arrived

View attachment 1273691
Click to expand...
Wow that was quick. May we should develop some kind of breadboard test using an Arduino for these. I doubt any of the chip testers support them.

Ansgar Kueckes said:
@nullvalue probably you bought the last items for the crystal, stock seems empty right now :)

Just in case you prefer a pot closer the the original, DigiKey seems to provide the suitable parts, see https://www.digikey.com/en/products/detail/tt-electronics-bi/91AR500LF/3587322
Click to expand...
I will have 1 spare of the crystals since it was sold as a set of 2. Thanks, I like the thumb wheel design of that pot, looks like mouser carries it too - I'll update the project. https://www.mouser.com/ProductDetail/858-91AR500LF

Ansgar Kueckes said:
Dazzler companion also just arrived
Click to expand...
I'm going to be needing one of those myself. A JS-1 would be nice too. Funny thing is, I somehow own the top edge connector piece for the D+7A but not the board itself.. :unsure:
 
Ansgar Kueckes said:
@nullvalue probably you bought the last items for the crystal, stock seems empty right now :)
Click to expand...

3.58MHz crystals in the HC-6/U can are still widely available as "new old stock" since they were very commonly used back in the pre-transistorized color TV era. If you do a web search on NTE358A (the crystal Hugo used) or NTE358B (the alternate) you can find many shops that still have stock.

See also eBay item number 305112711772 for the NTE358A - currently has 3 in stock.
 
I steer completely away from that type of preset with the grey thumbwheel and the ceramic base. They were used extensively in Tek scopes, of the 465/464/466 era and they are the only type of presets in the scope that give significant trouble. The reason is, unlike the enclosed case Bourns style presets, they are not sealed to the ingress of fumes and humidity and they nearly always become intermittent (mind you it does take a long time). Even after cleaning they give trouble again later on. One of my future projects is to replace those in all my Tek scopes. The other issue with the thumbwheel type they are easily bumped out of positional handling the pcb.

The better part for the Dazzler is the one with the rear facing slot in a sealed enclosure.
 
Thanks for the hint wit the NTE358A, I have used the eBay item number supplied.

Here are more possible eBay sources (all currently on vacation): item 295152149638 and item 234756505581
 
Hugo Holden said:
I steer completely away from that type of preset with the grey thumbwheel and the ceramic base. They were used extensively in Tek scopes, of the 465/464/466 era and they are the only type of presets in the scope that give significant trouble. The reason is, unlike the enclosed case Bourns style presets, they are not sealed to the ingress of fumes and humidity and they nearly always become intermittent (mind you it does take a long time). Even after cleaning they give trouble again later on. One of my future projects is to replace those in all my Tek scopes. The other issue with the thumbwheel type they are easily bumped out of positional handling the pcb.

The better part for the Dazzler is the one with the rear facing slot in a sealed enclosure.
Click to expand...
Haha dang well it's up to the builder to choose whichever pot they want. Personally, I think I'm going to stick with my first part. May not be ideal for making adjustments on the fly but once you get it dialed in I hope not to have to mess with it too much. Besides, it'll be the perfect excuse to use my benchtop motherboard revision.
 
daver2 said:
I have uploaded the two files:

cromemco.emu
DAZLIB.z80

The source code is designed to be assembled with the online assembler at asm80.com.

I have been using the cromemco.emu to test the code out. Hence some testing with real hardware would spur me on a bit more!

DAZLIB.z80 is a combination of a library and a test program.

Note that the memory EQUates may need to be changed for a physical machine.

There are a number of macros for interfacing to the library:

XINIT, XPLOT, XCLS, XMSG and XWAIT are the main ones.

XINIT initialises the library. Specify the desired mode, the address of the screen memory and the default background colour.
XPLOT plots a single point at an X/Y coordinate in a given colour.
XCLS clears the screen to the specified colour.
XMSG outputs the specified text to the console.
XWAIT Waits for a 'P' keyboard response before returning and proceeding.

The MSGOUT and PROCIN subroutines will require modifying to change the 'serial interface' from my cromemco.emu file to the real hardware.

I can help here if you let me know...

Dave
Click to expand...
Ok so I'm having a little trouble getting started here, I guess I don't really know where to begin with the emulator.. I assume you're using z80pack? I'm on Windows, and the window build don't seem to include the cromemcosim. Can I get a few "getting started" pointers for emulating the Dazzler?
 
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