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Re: New Board Development - SBC6120-RBC Edition [message #756 is a reply to message #755] Mon, 06 June 2016 12:06 Go to previous messageGo to next message
davetypeguy is currently offline  davetypeguy
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Hurray! I was able to finish the "6th" of the 5 prototype boards over the weekend. I installed the jumper fix on the back, and finally received the missing part I was waiting on (vendor shipped the wrong chips and had to replace them). I had issues with the terminal acting up, but after reading Will's description of his problem being due to a bad GAL, I reprogrammed the GALs with my "new" old Advin programmer ($100 used from eBay) and it cleared up the issues. Highly recommended, by the way, if you can get one reasonably priced. I still have the TL866 if I need it, but the Advin just seems to work without issue.

I still have to test out the IDE port (will look into making image tonight), but the leds are progressing through the proper sequence and I am able to enter monitor commands. I am ordering another oscillator to test it at 8MHz, just to see if it will work. BTW, I bought my 6120 from UTSource and the 6402 from Jameco. Both appear to be fine.
Re: New Board Development - SBC6120-RBC Edition [message #760 is a reply to message #548] Wed, 08 June 2016 05:33 Go to previous messageGo to next message
w9gb is currently offline  w9gb
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Andrew -
Beautiful layout. Feedback from initial prototype testers?

Greg

[Updated on: Wed, 08 June 2016 05:34]

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Re: New Board Development - SBC6120-RBC Edition [message #777 is a reply to message #760] Sat, 11 June 2016 10:50 Go to previous messageGo to next message
Andrew B is currently offline  Andrew B
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All of the credit for the overall layout goes to Bob Armstrong @ Spare Time Gizmos for creating the design and making it available for others to use. I've re-captured the schematic into KiCAD and made a few tweaks (and some mistakes on the prototype boards!) but I can't take credit beyond that.

Attached are schematics and board plot files for V1.00. Please take a good look over the next day or two everyone - especially at the ROM address pins!. My plan forward is the following:
-Update the wiki page w/final information on V1.00, with a sub-page documenting the 0.99 board ECNs in case anyone forgets later on
-Do a small run (~5 is the lowest number that makes sense costwise) of 1.00 boards with EasyEDA and build one up on my side to confirm the tweaks we made are working, the fixed ROM data line order, offboard reset switch, PTCC for feeding power to IDE->CF adapters, etc.
-Take names for a larger batch here, on the VCF forum, and on the STG Yahoo group
-Do a larger run with PCBCart - since they save the tooling it makes future repeat orders less expensive.

I have also been mulling over offering sets of HD-6120/HD-6402 or HD-6120/HD-6402/GALs/EEPROMs. This is certainly a hobby project and I don't want people to expect a ton of hand-holding in building their boards...so maybe that's not such a great idea? What do you guys think?

[Updated on: Sat, 11 June 2016 10:50]

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Re: New Board Development - SBC6120-RBC Edition [message #780 is a reply to message #777] Sun, 12 June 2016 02:01 Go to previous messageGo to next message
rhkoolstar is currently offline  rhkoolstar
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Hi Andrew,

Looking over your work, as per request, I found a few points of interest on the board:

I would assume that J2 (IDE) pin 20 - F2 -J16 pin 2 (essentially the IDE VCC input) should be in the SUPPLY net class.
I would move the extra RESET connector J17 slightly more inward, as the connections now are routed outside of the board margin.
Suggest rotating C8, C9 and C19 to locate them better to the VCC pins
Carried over from the original design: decoupling cap C12 is ineffective, as the VCC pin of U18 (52C55A) is pin 26. The cap should be located near this pin.
Maybe you should assign 'keepout' areas around the mounting holes, as several traces run the risk of being compromised by mounting hardware

I think the schematics are sound. I have been imitating your work; converting the original into kicad. Very instructional, and it makes checking a lot easier.
I would have wired the datalines of the RAM identical to the ROM (6 lines per IC and "big-endian") but there is no need to introduce cosmetic changes like this, running the risk of newly introduced errors.
Also I made library components for the HD-6120, HD-6402, 52C55A and GALs, conforming to Bob Armstrongs original layout. Additionally I used the 628128 component for the RAM. Maybe this is something you would want to use for the "release" schematics.

I attached my library in case you are interested.

RHK
  • Attachment: SBC6120.lib
    (Size: 10.26KB, Downloaded 514 times)

[Updated on: Sun, 12 June 2016 02:29]

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Re: New Board Development - SBC6120-RBC Edition [message #787 is a reply to message #454] Sun, 12 June 2016 09:19 Go to previous messageGo to next message
will is currently offline  will
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>offering sets of HD-6120/HD-6402 or HD-6120/HD-6402/GALs/EEPROMs

I found the HD-6120 the only part that was hard to source. I had issues programming the GALs (the Atmel parts I had ordered were not supported by my programmer).

I think offering the HD-6120 and programmed GALs and EEPROMs would be a good idea and would make the board accessible to many more builders.
Re: New Board Development - SBC6120-RBC Edition [message #804 is a reply to message #780] Sun, 12 June 2016 21:09 Go to previous messageGo to next message
Andrew B is currently offline  Andrew B
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rhkoolstar wrote on Sun, 12 June 2016 02:01
I would assume that J2 (IDE) pin 20 - F2 -J16 pin 2 (essentially the IDE VCC input) should be in the SUPPLY net class.


It should be, updated this. I'll need to re-route the board in Freerouting as a result, so let's get any final changes in now!

Quote:
I would move the extra RESET connector J17 slightly more inward, as the connections now are routed outside of the board margin.


Also a good suggestion, I moved this inward and away from U21 a hair as well.

Quote:
Suggest rotating C8, C9 and C19 to locate them better to the VCC pins


I rotated C9 & C19, but C8 is in the correct orientation for U11 (IOT 2 GAL) vs U21 (flip-flops for POST LEDs). U11 is more important, so I left C8 as-is.

Quote:
Carried over from the original design: decoupling cap C12 is ineffective, as the VCC pin of U18 (52C55A) is pin 26. The cap should be located near this pin.


The original design was 4 layers so all the capacitors are basically working together as capacitance between the 2 inner layers (power/GND). I'll go ahead and move this over for the benefit of our new 2-layer design.

Quote:
Maybe you should assign 'keepout' areas around the mounting holes, as several traces run the risk of being compromised by mounting hardware


The original board has traces routed near the holes, and the FP6120 manual specifies the use of nylon mounting hardware. I'd rather not constrain the Freerouting algorithm any more than I have to.


Re: New Board Development - SBC6120-RBC Edition [message #811 is a reply to message #804] Mon, 13 June 2016 09:28 Go to previous messageGo to next message
Andrew B is currently offline  Andrew B
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After making the updates mentioned, the board re-routed down to only 41 vias (10 less than the prior run!). I think rotating the 2 caps and moving C12 made the larger SUPPLY-class traces simpler and opened up more room to route the other traces.

I'll get new .pdfs out for everyone to review late this evening, but things are looking pretty good!

[Updated on: Mon, 13 June 2016 09:29]

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Re: New Board Development - SBC6120-RBC Edition [message #815 is a reply to message #811] Mon, 13 June 2016 10:14 Go to previous messageGo to next message
djones60 is currently offline  djones60
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Sounds great. Making some real progress.

I'll also second the other comment about the 6120/GAL/EPROM's. Not everyone will need them but I can see where some would.
Re: New Board Development - SBC6120-RBC Edition [message #816 is a reply to message #815] Mon, 13 June 2016 11:31 Go to previous messageGo to next message
gkaufman is currently offline  gkaufman
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Looks great.

Happy to help with burning GAL's and EPROM's for folks as needed.
Thankfully the 6120's are easy to source now thru Ebay or UTSource.

Only a minor suggestion to very clearly mark U11 as in reversed orientation. It's easy to forget and destroy a GAL (from experience)...

- Gary
Re: New Board Development - SBC6120-RBC Edition [message #824 is a reply to message #454] Wed, 15 June 2016 22:32 Go to previous messageGo to next message
Andrew B is currently offline  Andrew B
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Updated file are attached, based on rhkoolstar's feedback.

Take a final look over the next day or two, and then I'll be ordering handful of these from EasyEDA.

Still planning to do the larger batch with PCBCart to get nicer boards in the end.
Re: New Board Development - SBC6120-RBC Edition [message #825 is a reply to message #824] Thu, 16 June 2016 00:10 Go to previous messageGo to next message
rhkoolstar is currently offline  rhkoolstar
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Hi Andrew,

Looking good I'd say.

One last (cosmetic) remark: Note 1 on the top level sheet is no longer valid Razz. Sorry for not noticing this before...

I would like to be considered for one of the boards if possible. I have all of the parts available, including programmed GALs and EPROMs.
Testing should not take long.

RHK
Re: New Board Development - SBC6120-RBC Edition [message #831 is a reply to message #454] Sat, 18 June 2016 11:32 Go to previous messageGo to next message
Andrew B is currently offline  Andrew B
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Okay, since there are no other comments I'm going to fix Note 1 on the schematic and remove the 'Draft' designation and call this v1.00.

I'll order 5 v1.00 boards from EasyEDA. These will be green solder mask / HASL finish / 2 oz cooper. I need 1 to build up and test here, rhkoolstar gets 1 so we can add a new person testing v1.00 & the 'mini front panel' can get tested, and there will be 3 left. If anyone else is interested in building up 1 of those three v1.00s, let me know. I am 99% sure the layout is correct now, but we might still find some small tweaks are needed.

Once I can test a v1.00 board, I'll do posts in the Yahoo group, VCF DEC forum, etc to collect names for a larger run from PCBCart. I am leaning toward offering the HD-6120/HD-6402/EEPROM/GAL kits as well - probably as a 1-time run for now due to the time involved in programming/testing. I plan to add ZIF sockets stacked on top of my board so I can test the chips as a set before sending them out.
Re: New Board Development - SBC6120-RBC Edition [message #832 is a reply to message #831] Sat, 18 June 2016 12:06 Go to previous messageGo to next message
w9gb is currently offline  w9gb
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Andrew,
Great. I will hold-off on acquiring the HD-6120 ... since you will be sourcing those 4 parts.

greg
Re: New Board Development - SBC6120-RBC Edition [message #833 is a reply to message #832] Sat, 18 June 2016 13:41 Go to previous messageGo to next message
rhkoolstar is currently offline  rhkoolstar
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I'm pretty sure you've got it right. I've been putting Bob Armstrong's schematics into Kicad too (without "peeking"), and I could not spot any meaningful differences between your and my renditions. It is a great way to find out how things work.

After I validate my GALs and EPROMS I'll be happy to partake in providing programming services. It would be great if we could have "localized services" to keep the cost of postage to a minimum.
Re: New Board Development - SBC6120-RBC Edition [message #834 is a reply to message #833] Sat, 18 June 2016 14:20 Go to previous messageGo to next message
gkaufman is currently offline  gkaufman
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If there are spares I'd be happy to put together one of the V1.0 boards. I have all of the parts here already.

Also happy to help with distributing GAL's and EPROM's.

Should we look into making an image of the OS-8 Compact Flash disk available? I can't recall where I cobbled mine together from.
Running Adventure on vintage hardware is one of the best features of bringing this all together!

- Gary
Re: New Board Development - SBC6120-RBC Edition [message #835 is a reply to message #834] Sat, 18 June 2016 14:45 Go to previous messageGo to next message
rhkoolstar is currently offline  rhkoolstar
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I believe they are on the Spare Time Gizmos website? http://www.sparetimegizmos.com/Hardware/SBC6120_Builders.htm , under RESOURCES
Re: New Board Development - SBC6120-RBC Edition [message #836 is a reply to message #835] Sat, 18 June 2016 14:52 Go to previous messageGo to next message
Wayne W is currently offline  Wayne W
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Might be the same images, but in case it helps, I got my OS-8 image from GRC at https://www.grc.com/pdp-8/os8utils-sbc.htm.

-Wayne
Re: New Board Development - SBC6120-RBC Edition [message #837 is a reply to message #836] Sat, 18 June 2016 15:22 Go to previous messageGo to next message
Andrew B is currently offline  Andrew B
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I am going to dump an image of both the OS/8 OS and GAMES disks that Win32DiskImager can write directly to a CF card, to make it easier for people to get going.
Re: New Board Development - SBC6120-RBC Edition [message #838 is a reply to message #837] Sat, 18 June 2016 21:20 Go to previous messageGo to next message
Andrew B is currently offline  Andrew B
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The OS/8 and Games files that are linked on the STG page and the ones at the GRC page have identical file sizes/creation dates back in 2002, so I believe they are the same files.

I've attached a 'combined image' that can be written all at once to a CF card using Win32DiskImager or dd. This was pretty easy to make, just concatenate the two .ide files into one file.

I did try to put the Adventure files on the system disk using FLX8, but it doesn't seem to run. Once I get that worked out I will post an updated image.
Re: New Board Development - SBC6120-RBC Edition [message #840 is a reply to message #838] Tue, 21 June 2016 08:00 Go to previous messageGo to next message
rhkoolstar is currently offline  rhkoolstar
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Andrew,

Could I bother you for the location of the mounting holes, expansion connector and the CPREQ jumper on the board? They can be extracted from the .kicad.pcb file.

With these, I can verify the physical layout of the front panel logic and order prototypes without having to wait for the CPU board to arrive.

RHK
Re: New Board Development - SBC6120-RBC Edition [message #903 is a reply to message #840] Mon, 04 July 2016 20:07 Go to previous messageGo to next message
Andrew B is currently offline  Andrew B
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Sorry it took me so long to get back to you - attached is an updated board layout .pdf with additional dimensions added to the 'Dwgs.User' sheet to show the mounting hole and CPREQ locations.

Let me know if you need anything else.
Re: New Board Development - SBC6120-RBC Edition [message #925 is a reply to message #903] Sun, 10 July 2016 20:06 Go to previous messageGo to next message
Andrew B is currently offline  Andrew B
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Rev 1.00 test batch boards will be here Tuesday! Thanks everyone for all the feedback on this one, I'll post some pictures when I get them.
Re: New Board Development - SBC6120-RBC Edition [message #977 is a reply to message #925] Wed, 20 July 2016 07:47 Go to previous messageGo to next message
gkaufman is currently offline  gkaufman
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Any update on the Rev 1.00 boards?
Re: New Board Development - SBC6120-RBC Edition [message #981 is a reply to message #977] Wed, 20 July 2016 12:37 Go to previous messageGo to next message
Andrew B is currently offline  Andrew B
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The five small-run boards are here, one is sitting on my desk partly built.

Once I can check it out a bit, I will be collecting names for the larger run.

[Updated on: Wed, 20 July 2016 12:37]

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Re: New Board Development - SBC6120-RBC Edition [message #1025 is a reply to message #454] Tue, 02 August 2016 13:01 Go to previous messageGo to next message
Andrew B is currently offline  Andrew B
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Things are finally wrapping up with my house sale so I should get the V1.0 board finished up this week.

I didn't get a table at VCF West but I'll probably bring it with me just in case.


Re: New Board Development - SBC6120-RBC Edition [message #1085 is a reply to message #454] Sat, 03 September 2016 22:19 Go to previous messageGo to next message
Andrew B is currently offline  Andrew B
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Finished building the 1.00 board tonight and it booted up with the stock, non-scrambled v320 ROM files on the first try!

I need to finish testing the new features we added:
-External reset switch header
-Powering IDE->CF Adapter on Pin 20 (I plan to measure current used so I can recommend an appropriate picofuse)
-28C256 EEPROM/27C256 EPROM J15 config - EEPROM works for sure, need to test the v271 EPROMS out of my STG board to confirm that works as well.
-Try John's troublesome '373 chips to make sure the new routing improved stability of the board.

Should get that wrapped up tomorrow.
Re: New Board Development - SBC6120-RBC Edition [message #1086 is a reply to message #1085] Sat, 03 September 2016 22:37 Go to previous messageGo to next message
Wayne W is currently offline  Wayne W
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Nice. Congrats Andrew.

-Wayne
Re: New Board Development - SBC6120-RBC Edition [message #1087 is a reply to message #1086] Sun, 04 September 2016 00:48 Go to previous messageGo to next message
will is currently offline  will
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Andrew -- great work!

For the IDE power polyfuse I recommend a 500mA PPTC (see table 7 of http://rumkin.com/reference/aquapad/media/cfspc3_0.pdf)

[Updated on: Sun, 04 September 2016 00:48]

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Re: New Board Development - SBC6120-RBC Edition [message #1088 is a reply to message #1087] Sun, 04 September 2016 09:10 Go to previous messageGo to next message
gkaufman is currently offline  gkaufman
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Fantastic!
Re: New Board Development - SBC6120-RBC Edition [message #1089 is a reply to message #1087] Sun, 04 September 2016 10:18 Go to previous messageGo to next message
Andrew B is currently offline  Andrew B
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The main fuse for the entire board is a 0.5A fuse, so in my mind the CF card picofuse should be something less than that.

The CF card power consumption is largely going to depend on how fast data is being transferred, and we are only using PIO mode to access the so I doubt that the power consumption will exceed the original Power Level 0 values by much.

This Transcend datasheet has some power numbers for their card - http://docs-europe.electrocomponents.com/webdocs/1111/090076 6b8111177c.pdf - max at 5V is 173mA for write and 152mA for read, in UDMA4 mode.

Sandisk has some numbers at -https://media.digikey.com/pdf/Data%20Sheets/M-Systems%20Inc %20PDFs/SanDisk%20CompactFlash%20Memory.pdf - max average 100mA at 5V

I think something like 250mA would be a good CF card picofuse setting.
Re: New Board Development - SBC6120-RBC Edition [message #1092 is a reply to message #1089] Mon, 05 September 2016 19:57 Go to previous messageGo to next message
Andrew B is currently offline  Andrew B
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Completed testing of the following items:
-External reset switch header - works OK
-Powering Syba SD-CF-IDE-DI via power on Pin 20 - works OK
-28C256 EEPROM / 27C256 EPROM switching with J15 - works OK (tested with EEPROMs from original STG board & new EPROMs)
-The 74ACT373 chips that would not boot in the 0.99 board (unless the board was place on a non-conductive sheet on top of a metal foil sheet) - boot OK with the v1.00 board routing!

I stress tested the board with both 74HC373s and the formerly problematic 74ACT373s by running a small BASIC program to calculate the Fibonacci Sequence all the way to the largest number handled by the OS/8 BASIC. No problems.

I think I am going to make one change to the silkscreen on the final v1.00 production boards to add a note about J16 / F2 being optional.

Otherwise this is looking good. I'll work on updating the wiki page with more information this week & by next weekend hope to be collecting names for a big run of boards.

[Updated on: Mon, 05 September 2016 19:58]

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Re: New Board Development - SBC6120-RBC Edition [message #1096 is a reply to message #1092] Wed, 07 September 2016 15:19 Go to previous messageGo to next message
martin8bity is currently offline  martin8bity
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Great work! Congratulations!

www.8bity.cz
Re: New Board Development - SBC6120-RBC Edition [message #1101 is a reply to message #1096] Thu, 08 September 2016 09:03 Go to previous messageGo to next message
Andrew B is currently offline  Andrew B
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The credit really goes to Robert Armstrong for creating and making available the design & everyone who helped me test the 0.99 boards. All I really did was turn the crank on KiCAD on this one.

[Updated on: Thu, 08 September 2016 09:04]

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Re: New Board Development - SBC6120-RBC Edition [message #1188 is a reply to message #1101] Mon, 26 September 2016 09:03 Go to previous messageGo to next message
Andrew B is currently offline  Andrew B
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Attached is a fun new image file for writing to a CF card using Win32DiskImager or dd. With the latest (2014) updated version of OS/8 Adventure!

It has two drives - SYS:/DSK: (same drive) is the OS/8 / source code / compiled binary image from Rick Murphey's Adventure site and IDA1: is the BASIC games image from the original Spare Time Gizmos site.

To run Adventure:
.R FRTS <enter>
*ADVENT <enter>
*<ESC>
<Wait approximately 1 minute, 15 seconds for game to load>

To list the BASIC games on IDA1:
.DIR IDA1:

To run the BASIC games on IDA1:
.COMPILE IDA1:<FILENAME> <ENTER>
<Wait for game to load>

For a list of all the BASIC games, see the 2nd directory listing on https://www.grc.com/pdp-8/os8-sbc.htm

Also on SYS: on this version of OS/8 is a version of the TECO editor that uses VT100 escape codes to move the cursor around the screen, etc - I haven't played with that too much but it seems like it could be pretty useful.

(This is a somewhat later version of OS/8 'V3T' than the one in the other SBC6120 images 'V3Q', for some reason running BASIC directly does not seem to work properly but using COMPILE does even though it doesn't actually compile anything - if anyone can figure this out it would be greatly appreciated. The version of FORTRAN IV on the original SBC6120 OS/8 image was missing PASS2O.SV and could not compile Adventure, which took some trial and error to get running, so I created the new image instead using a version I knew would work.)

[Updated on: Mon, 26 September 2016 09:04]

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Re: New Board Development - SBC6120-RBC Edition [message #1242 is a reply to message #454] Sat, 15 October 2016 13:26 Go to previous messageGo to next message
Andrew B is currently offline  Andrew B
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I noticed something strange in my testing. Out of 3 different brands/types of CF cards that I tested, 1 card hangs on bootup:

-Random Canon 32MB card that was a pack-in with a digital camera in 2005 - OK
-Kingston 4GB card 'CF/4GB' - OK
-SanDisk Ultra 4GB 25MB/s - HANGS

The first thing I tried was soldering a 22uF capacitor to the bottom of the board between J2-Pin 20 (CF card power) and GND, thinking maybe the CF card needed some additional decoupling. But that didn't seem to help.

The next thing I checked was the voltage making it to the CF card - only 4.73V! Then I checked directly on the output of the main board fuse (F1) and found that that voltage was only 4.73V. There was over 300mA of voltage drop across F1. Interesting.

So I made some measurements of the STG SBC6120 and the SBC6120-RBC Edition Rev 1.00 (without the CF card drawing power):
-STG SBC6120 - current draw ~103 mA, F1 resistance 1.3 ohm, voltage drop across F1 = .133 V, voltage at IC Vccs = 5.04 V
-SBC6120-RBC Edition 1.00 - current draw ~207 mA, F1 resistance 1.5 ohm, voltage drop across F1 = .310 V, voltage at IC Vccs & CF card = 4.83 (!) V

Hm, interesting, the RBC Edition is drawing 2x the current of the original STG board. I wonder why?

I narrowed the issue down to the GALs. My new Rev 1.00 board was using Lattice GALs, while the original STG chips are the lowest-power version of the Atmel ATF chips. A final measurement with switched chips confirmed this:
-SBC6120-RBC Edition 1.00 w/STG Atmel GALs - current draw 105 mA, F1 resistance 1.5 ohm, voltage drop accross F1 = .157 V, voltage at IC Vccs & CF card = 4.97 V - SanDisk CF card boots OK!

There's a couple potential solution here for people wanting to power their cards on Pin 20:
-Use the lower-power Atmel ATF GALs (ATF16V8BQL-15PU & ATF22V10CQZ-20PU) to keep the overall board current draw and hence the voltage drop across F1 lower
-Install a fuse with a lower nominal resistance, for example a .750 A fast-blow fuse ( http://www.littelfuse.com/~/media/electronics/datasheets/fus es/littelfuse_fuse_251_253_datasheet.pdf.pdf) has a nominal resistance of only .175 ohms.

On further consideration though - I do think additional decoupling of the CF card is prudent & I have gone ahead and added a location for another 47 uF capacitor just *after* the fuse, just before J2-Pin 20.

That rolls the Rev to 1.10, it should the last change before we go to mass production!
Re: New Board Development - SBC6120-RBC Edition [message #1247 is a reply to message #1242] Sat, 15 October 2016 15:32 Go to previous messageGo to next message
sparetimegizmos is currently offline  sparetimegizmos
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Quote:
the RBC Edition is drawing 2x the current of the original STG board. I wonder why?


More GALs. As you figured out, the 22V10 chips are fairly power hungry...

Bob
Re: New Board Development - SBC6120-RBC Edition [message #4000 is a reply to message #1247] Sat, 23 December 2017 07:38 Go to previous messageGo to next message
will is currently offline  will
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Hey

Just got out my SBC6120 today to write some software.

Can't seem to get it to run even simple BASIC programs. I'm using the "sbc6120_firstrun_25sept2016.img" disk image from the RBC wiki. Tried a couple of CF cards with the same results.

I know on this first PCB rev some of the decoupling caps are not correctly connected so I've added extra decoupling on the rear of the board between VCC/VSS on the CPU, RAMs, UART, 8255, and all three GALs. No change.

Here's a log of what I see:

(hardware reset)
SBC6120 ROM Monitor V271 Checksum 3732 7215 6243  15-APR-04 10:28:05
Copyright (C) 1983-2004 Spare Time Gizmos.  All rights reserved.

NVR: 0KB - Battery FAIL
IDE: 2001MB - SILICONSYSTEMS INC 2GB                 

>B
-IDA0

.R BASIC
NEW OR OLD--NEW
FILE NAME--FOO

READY
10 PRINT "HELLO WORLD"
20 GOTO 10
RUN

FOO     BA    7A    


?Halted at 17403
PC>7403 PS>1011 AC>0000 MQ>0000 SP1>0000 SP2>0000 

>
(hardware reset)
SBC6120 ROM Monitor V271 Checksum 3732 7215 6243  15-APR-04 10:28:05
Copyright (C) 1983-2004 Spare Time Gizmos.  All rights reserved.

NVR: 0KB - Battery FAIL
IDE: 2001MB - SILICONSYSTEMS INC 2GB                 

>B
-IDA0

.BASIC
NEW OR OLD--NEW
FILE NAME--FOO

READY
10 PRINT "HELLO WORLD"
20 GOTO 10
RUN

FOO     BA    7A    


?Panel trap at 67777
PC>7777 PS>1066 AC>1035 MQ>0000 SP1>0000 SP2>7777 

>


Note the only different between the two sessions above is how BASIC is invoked - "R BASIC" versus just "BASIC". Not entirely sure what the difference is. Each fails in its own way, consistently.

Any suggestions for what is wrong or what I might try?

PS behaviour is identical with CPU clocked at 5MHz and 8MHz, and with two different power supplies (rated 3A and 2.5A; board draws only 0.2A)

[Updated on: Sat, 23 December 2017 07:44]

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Re: New Board Development - SBC6120-RBC Edition [message #4001 is a reply to message #454] Sat, 23 December 2017 08:05 Go to previous messageGo to next message
Andrew B is currently offline  Andrew B
Messages: 467
Registered: October 2015
Location: Near Redmond, WA
Senior Member
Administrator
Will - it's much more likely that this is a problem with my image file than with you hardware.

I'm honestly not much of an OS-8 expert and my focus with that image was fixing some FORTRAN issues so I could compile/run the latest version of PDP-8 Adventure on it.

I thought I had tested some of the BASIC games and they ran fine though.

I'll burn a fresh image and try the same set of commands and see what I get back.

[Updated on: Sat, 23 December 2017 08:13]

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Re: New Board Development - SBC6120-RBC Edition [message #4002 is a reply to message #4001] Sat, 23 December 2017 08:34 Go to previous messageGo to next message
will is currently offline  will
Messages: 213
Registered: October 2015
Senior Member
Ah, clever chap.

Switched to using "SBC6120.ide" downloaded from grc.com and BASIC is working (once I'd figured out what "ME 10" meant!)

LIST

FOO     BA    5B    

10 FOR A=1 TO 5
20 PRINT "NUMBER"; A
30 NEXT A
40 END

READY
RUN

FOO     BA    5B    

NUMBER 1 
NUMBER 2 
NUMBER 3 
NUMBER 4 
NUMBER 5 

READY


Much better!

[Updated on: Sat, 23 December 2017 08:34]

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Re: New Board Development - SBC6120-RBC Edition [message #4003 is a reply to message #4002] Sat, 23 December 2017 08:45 Go to previous messageGo to previous message
Andrew B is currently offline  Andrew B
Messages: 467
Registered: October 2015
Location: Near Redmond, WA
Senior Member
Administrator
I'm glad the problem was on my end.

I'll see about fixing my image file.
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