The Compact Computer 40 (CC40)

[brain]

Hi Jim,

OK, I just got home from work.

,

Using the standard ruler. The height of the Cart, ( top edge to bottom

Of cart at the edge connector is 61/32 or 3/32 short of 2 Inch total.

,

The main board is 1 inch and 15/32 or 47/32 or 1 inch and half inch minus 1/32

,

From the main board edge to the cart edge connector is 14/32 or 2/32 short of 1/2 inch.

,

Adding these all together 47/32 + 14/32 = 61/32 or 3/32 short of 2 inch total height.

,

Also using this 47/32, measure from the top edge of the cart to the center of

The first tabs , = 9/32 , measure from center of first tab to center of second

Tab , = 29/32 , then measure from center of second tab to bottom edge of

Main part of cart , = 9/32. Add them up 9/32 + 29/32 + 9/32 = 47/32

And if we add in the edge connector part 14/32 we end up with 61/32

Or 3/32 short of 2 inch's.

,

Again I hope this is useful

Lee TI998owner

 

I modified the PCB to suit. I had to chop a bit off the bottom (by the edge connector) to have it match your measurements, so I'd like to check the measurements (I'd like to have the PCB be as large as possible, as newer designs may need the little bit of extra PCB).

 

The original PCB was 1.50" as the main box, but it was .05 too short (1.85" instead of 61/32 or 1.90"). The main part of the PCB was 1.50". I increased the 1.85 to 1.90, but then had to chop .1 off (1.46" instead of the new 1.55"). I'd like to see if I can put that .1" back on

 

Jim

Edited December 12, 2017 by brain

[TI998owner]

Hi Jim,

OK, the picture looks good. About the .1 of space

That should be no problem. As a matter of actual

Fact. Depending on the design of the 3D replacement

Case. You could make the CC-40 cart longer by about

1/4 inch or 8/32 . There is room in the cart slot,

But the new plastic case may reduce this space a bit.

,

Also the cart edge connector on the new boards are

Shorter by 3/32 of a inch then the original TI

Produced boards. But this fact , does not seem

To be any problem. As all of the boards I received

So far are working, very good.

,

The extra space I am talking about ( 8/32 ) is

With the cart slot cover in place.

Also an interesting fact, one of the 3d party

Carts for the CC-40 . Board designed by

Digital Matrix Systems, code date on the cart PC board

Of ( 05/ 1983 ). Produced on ( 12/06/1985 ).

,

Is 1 and 3/4 inch wide , no tabs. The board is 60/32

In height . and the main part of the cart is 47/32,

Minus the cart edge connector part.

,

The plastic case is square and the cart fits like a glove.

,

Lee TI998owner

[+acadiel]

Can I ask again why we are leaving legacy PCB tabs on these new boards? I see no reason why they should be there other than to fit in legacy cases. I don’t plan on supporting them in my 3D models. My model was already underway when this tab discussion came out of nowhere.

[brain]

Can I ask again why we are leaving legacy PCB tabs on these new boards? I see no reason why they should be there other than to fit in legacy cases. I don’t plan on supporting them in my 3D models. My model was already underway when this tab discussion came out of nowhere.

They help with alignment and keeping the board from shifting in the enclosure. I am not sure the board will be held in place enough without them in a legacy case, though I can delete them if desired.

 

Jim

[+acadiel]

I think part of the problem is that the old cartridge shell was 44.25mm across inside, and that the old board was 43.15mm across. This left 1.1mm of wiggle room, which is just enough to be annoying and move around. The Mechatronics cartridge didn't have the tabs, and the PCB was secured very well inside of it.

 

I have two working theories for snapping them together right now; one is a very snug press fit (like the current TI ones, but snug enough to press together to where the pieces will just not want to fall apart), and snap fit joints (which I didn't have luck with last time I designed the TI shells, which is why I moved those to a three screw solution).

 

The top of the shell will be snug against the top of the IC, and the surface area of that IC is enough to keep it from wobbling around. 11.75mm thick is what I'm reading with the solder pins to the top of the IC on the current boards. The prototype boards I have are 38mm tall, and the the old shells were only 37.25mm tall, so I had to increase the shell length by .75mm. 43.20mm is what the proto boards are reading as across from left to right, so this is what I'm making the shell be inside (I'm making it like 43.22mm to I don't have to force push it inside.)

[brain]

OK, well, I will put the tabs in a separate file and not worry about them.

 

But, what is the correct size of the main PCB. I increased the overall height to the 1.90", and the kept the original distance from top of board to bottom, minus the edge connector, at the same value, giving 1.55" of PCB real estate. The actual old style boards only off 1.45". Which should I use?

[+acadiel]

Switching to mm for our European friends.

 

Main PCB dimensions of the my RAM cart (without the tabs). 48.25mm top to bottom including the fingers. 43.40mm from left to right. Fingers are around 11mm long (estimate).

 

Your v1 ROM board is 47.40mm top to bottom. 43.25mm from left to right. Fingers are 8.75mm long (estimate.)

 

Your PCB as is gives about 8.77mm between the tip of the switch and the case edge. If you take out the 2.95mm of the cover, that means the board could actually be 5.82mm taller than it is right now (minus whatever case overhead, which I'm still working on.)

 

Does that help?

[+acadiel]

Helocast, appears I got a good and bad one. And yeah, tried a different board and reseating them.

 

[brain]

I think what I'm wondering is what the max size should be.

 

43.25mm side to side sounds about as large as it can be and still allow you space to put a case on the sides

I was planning on making the board .05" (1.90", or 48.26mm). That would leave 8.77 - .86 = 7.91mm = .31" between the end of the board and the case edge.

 

Just wondering what the max board size should be.

 

Jim

[+helocast]

Helocast, appears I got a good and bad one. And yeah, tried a different board and reseating them.

Well, I suppose it's possible since they are just regular LP CMOS ram chips (with a lithium cell for backup).

Next set of V1+?/V2 boards, I won't socket it to get the height profile down to where they'll fit with the sliding cover on. I just though it was a comparable way to get rid of buying the ram and a coin battery for the ram-configured carts and I had a few on hand from Thiery's HAMS board project.

I hope your bad one was a just one off.

[+acadiel]

Well, I suppose it's possible since they are just regular LP CMOS ram chips (with a lithium cell for backup).

Next set of V1+?/V2 boards, I won't socket it to get the height profile down to where they'll fit with the sliding cover on. I just though it was a comparable way to get rid of buying the ram and a coin battery for the ram-configured carts and I had a few on hand from Thiery's HAMS board project.

I hope your bad one was a just one off.

 

Yeah, he's sending me a new replacement.

 

I have a rough frame for a new cartridge cover with a slightly higher IC profile inside Inventor right now. Plus, it's easy to make it flat again and make a model for a replacement cover

[brain]

Had some IRL stuff come up, and late to ordering new boards, but would like to tonight.

 

I am including a specification of the PCB as it now exists. A few notes (all dimensions in mm, unless otherwise noted):

 

• The largest dimensions are the cart opening size. I measure it to be 52.37 wide, but 47.70 deep
• But, with the cover on, the size shrinks a bit. 51.05 wide by 45.03 deep max
• As Lee notes, my edge connector fingers were a bit short. When PCBs are pressed into the socket, the PCB touches the cc40 by the edge connector, which does not leave any room for a case, as far as I can tell. I thus pushed the edge there a bit back, to 10.95 (it was 8.89). let me know if that was in error
• I removed the tabs, but left their dimensions in the file
• The two innermost dashed lines represent the enclosure. I used 2.54mm width for the sides, and 1.27 for the width of the front side (where the edge connector is), as 2.54mm ate into the new PCB dimensions, which I know were from you and Lee and fit in a real case. However, the only dimension I have for enclosure is the interior width of the enclosure, so it is represented. To determine the max height of the PCB, it would be nice to get interior and exterior dimensions of the enclosure, so I can work backward from the enclosure.

 

As it stands right now, with the PCB now 48.26 in height (1.90"), and assuming 2.54 (.1") enclosure width, and further assuming that the total height minus the edge connector cannot be more than 45.03, the PCB is getting close to max size.

 

If folks are up for a Skype call later tonight to iron out the rest of the dimensions in real time, I will ensure the order committed includes the adjustments.

 

Jim

[TI998owner]

Hi Jim,

,

I did some CC-40 Cart Case measures, from original

Texas Instruments carts. The inside part of the cart

Case shell measures.

,

Inside plastic shell = Width 1 and 3/4 inch or 56/32 inch or 4.4 MM

Inside plastic shell = Height 1 and 1/2 minus 1/32 inch or 47/32 inch or 3.7 MM

,

Outside plastic shell = Width 1 and 28/32 inch or 60/32 inch or 4.4 MM

Outside plastic shell = Height 1 and 19/32 inch or 51/32 inch or 4 MM

,

Also about the edge connector , you can increase the height to 14/32 inch

From the main part of the main cart board. Instead of the current 11/32 inch.

This should not affect the design of the main board and solve the problem

Of the size issue fitting into the current cart size.

,

Also about the current 3d cart design, that also should be able to be

Changed ( Size , Height of cart ) in future board layout if needed.

The only factor affecting this is the CC-40 cart slot cover.

,

Heck, if we decided to design a Solid state hard drive using the CC-40

Cart Slot connector the size of the ( height ) circuit board also

Would not be a factor. Because most people would love the added feature

At the expense of not putting the card slot cover on.

,

Hopeful we will have or get the Hexbus solid stage floppy interface

Board completed before the next idea ..... I.e CC-40 cart slot solid state hard drive.

,

Well hope this info helps

Lee TI998owner

[atrax27407]

For those who are interested, and lack the facilities to burn their own EPROMs of FLASH chips, I have a supply of chips and can do either the 27C040 or 39SF040. Send me a PM if you are interested.

[+acadiel]

Had some IRL stuff come up, and late to ordering new boards, but would like to tonight.

 

I am including a specification of the PCB as it now exists. A few notes (all dimensions in mm, unless otherwise noted):

 

• The largest dimensions are the cart opening size. I measure it to be 52.37 wide, but 47.70 deep
• But, with the cover on, the size shrinks a bit. 51.05 wide by 45.03 deep max
• As Lee notes, my edge connector fingers were a bit short. When PCBs are pressed into the socket, the PCB touches the cc40 by the edge connector, which does not leave any room for a case, as far as I can tell. I thus pushed the edge there a bit back, to 10.95 (it was 8.89). let me know if that was in error
• I removed the tabs, but left their dimensions in the file
• The two innermost dashed lines represent the enclosure. I used 2.54mm width for the sides, and 1.27 for the width of the front side (where the edge connector is), as 2.54mm ate into the new PCB dimensions, which I know were from you and Lee and fit in a real case. However, the only dimension I have for enclosure is the interior width of the enclosure, so it is represented. To determine the max height of the PCB, it would be nice to get interior and exterior dimensions of the enclosure, so I can work backward from the enclosure.

As it stands right now, with the PCB now 48.26 in height (1.90"), and assuming 2.54 (.1") enclosure width, and further assuming that the total height minus the edge connector cannot be more than 45.03, the PCB is getting close to max size.

 

If folks are up for a Skype call later tonight to iron out the rest of the dimensions in real time, I will ensure the order committed includes the adjustments.

 

Jim

Feel free to Skype me. Under Acadiel. If I don’t respond, try again as the wife has me doing honey do tasks in preparation for company.

[brain]

Feel free to Skype me. Under Acadiel. If I don’t respond, try again as the wife has me doing honey do tasks in preparation for company.

Added you as a contact. Accept, and I will call.

 

Jim

[brain]

OK, here are the revised boards. Changes since last set:

 

• Both carts have been resized to ensure they fit in a std case minus the screw hole
• RAM cart R6 has been corrected in the schematic. Still not sure it is needed (it holds the RAM a bit above GND when pulled out of the unit)
• pullups on RAM cart only operate when unit is plugged in (when unplugged, pullup on !CS will render address lines ignored anyway, so no need to pull them up and drain battery)
• 28 and 32 pin EPROM support added to ROM cart. 27C0XX is now the default
• diodes removed from ROM design
• Missing P25.2 and P25.3 signals added to extender cart
• Jumpers to enables P25.2 and P25.3 have been added to RAM and ROM carts. solder and do not use sw1/sw2 to enable. (might need pullups, no idea)

 

Jim

[brain]

So, what was decided about splitting this topic up? sub forum, different topics, etc? I am stuck on a development point on the SD drive, and would like to ask some questions, but not sure it will be found buried in this thread.

 

Let me know.

 

Jim

[TI998owner]

Hi Jim,

,

Can you check the PRInt layout on the extender board.

Comparing the first extender board to the new design

, it looks like the board has been turned around, with

The printing going the wrong way.

,

I.e like CROM and Vplug are on the end where A13 and GND

Were at on the first board run, if you compare the

Two board designs, for the extender.

,

Thanks, let me know

Lee

[brain]

Thanks for the catch.

 

Updates:

[+OLD CS1]

So, what was decided about splitting this topic up? sub forum, different topics, etc? I am stuck on a development point on the SD drive, and would like to ask some questions, but not sure it will be found buried in this thread.

 

Let me know.

 

Jim

 

I moved this thread to the development sub-forum. If the SD thread is in the general I can move it, too. As for a new sub-forum, that is something we would need to petition Albert to do for us. I do not know what his criteria are for making new subs, like number of existing or active posts on the subject, so I suppose it is worth the asking.

[+acadiel]

We probably want to split out the SD related posts into its own topic. Can that be done?

[+OLD CS1]

We probably want to split out the SD related posts into its own topic. Can that be done?

 

I will ask Albert this afternoon.

[+OLD CS1]

 

I will ask Albert this afternoon.

 

I have not yet received official instructions but I noticed tonight I have privileges to move and split posts. I will wait for proper guidance on these functions and then will split out the HexBus2SD (yeah, I named it, what you wanna do about it?) expansion.

[sometimes99er]

Actually, I think our TI section here on AtariAge is now large enough to accommodate a dedicated CC40 subgroup. With all this new activity from this new device, I think it deserves it. It would make a nice place for people to come for all things CC40 , hardware, software, modifications, etc.

Yes, please.