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Re: New Board Development - SBC6120-RBC Edition [message #5237 is a reply to message #5236]

Sat, 29 September 2018 14:37

boss
Messages: 4
Registered: October 2017

Junior Member

For me as well.

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Re: New Board Development - SBC6120-RBC Edition [message #5246 is a reply to message #5237]

Sun, 30 September 2018 10:49

Andrew B
Messages: 438
Registered: October 2015
Location: Hawthorne, CA

Senior Member
Administrator

I started a new thread on a simple Arduino checker to see if a chip is actually an HD1-6120:
https://www.retrobrewcomputers.org/forum/index.php?t=msg& ;th=328&start=0&

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Re: New Board Development - SBC6120-RBC Edition [message #5308 is a reply to message #5246]

Wed, 10 October 2018 14:22

gkaufman
Messages: 137
Registered: October 2015

Senior Member

Picked up 2 more HD-6120's from UTSOURCE. They were listed as D1-6120-9C
https://www.utsource.net/itm/p/1887077.html

They appear old (some oxidation on pins, minor chips in ceramic) but original and both work perfectly.

$14.19 each, and they list 75653 in stock!!!

- Gary

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Re: New Board Development - SBC6120-RBC Edition [message #5313 is a reply to message #4011]

Thu, 11 October 2018 14:44

scruss
Messages: 13
Registered: December 2015
Location: Toronto, Canada

Junior Member

will wrote on Tue, 26 December 2017 13:58

...
I measured the power consumption of my SBC6120, including IDE to CF adapter and CF card, as about 200mA. USB can easily deliver this.

Thanks for this. I may have to try it, as my recently-built SBC6120-RBC Edition successfully goes through POST but doesn't get to kick anything out the serial port. I suspect I may have fouled up the cabling. Or not found a terminal under Linux that can talk 7M1. 9-pin serial null-modems are much rarer beast these days than when the original SBC6120 came out.

One caveat about using FTDIs and the like is that - while USB can deliver 200 mA and beyond - they often negotiate to limit themselves to 100 mA. There's a milliamp rating (sometimes confusingly called "Max Power") in the USB parameters that shows you their current limit. SparkFun has a "Beefy" USB serial adapter that can deliver quite a bit more power, but is a lot more expensive.

> Does anyone know what each of the pins on the 6502 CPU chip in the Apple II Plus does?
They all plug into the socket on the motherboard to keep the chip from drifting away. - c.s.a2 FAQ of yore

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Re: New Board Development - SBC6120-RBC Edition [message #5314 is a reply to message #5313]

Thu, 11 October 2018 15:40

tingo
Messages: 76
Registered: February 2017
Location: Oslo, Norway

Member

FWIW, I found that simply doing 'screen /dev/ttyUSB0 9600' (or whatever your usb serial port is called) works. Of course, this was after I had spent some time trying to get usb-to-ttl adapters working (blush)...

Torfinn

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Re: New Board Development - SBC6120-RBC Edition [message #5315 is a reply to message #5314]

Thu, 11 October 2018 20:40

scruss
Messages: 13
Registered: December 2015
Location: Toronto, Canada

Junior Member

Aha! The null modem cable I bought turned out to be straight-through. On rectifying, the console message came through. Yeah! Another successful SBC6120-RBC is built!

> Does anyone know what each of the pins on the 6502 CPU chip in the Apple II Plus does?
They all plug into the socket on the motherboard to keep the chip from drifting away. - c.s.a2 FAQ of yore

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Re: New Board Development - SBC6120-RBC Edition [message #5320 is a reply to message #5315]

Sat, 13 October 2018 12:50

scruss
Messages: 13
Registered: December 2015
Location: Toronto, Canada

Junior Member

... though I shouldn't be too happy as I'm yet to get the thing to boot successfully.

I typically get the monitor prompt, but (B) isn't accepted:

SBC6120 ROM Monitor V320 Checksum 3752 6072 3515 09-APR-10 21:15:39
Copyright (C) 1983-2010 by Spare Time Gizmos. All rights reserved.

NVR: Not detected
IDE: 489MB - LEXAR ATA FLASH
IOB: Not detected

>BBBBBBBBB
This is just from pressing B once.

I did get a card to boot once, but unfortunately my serial params were wrong and all I got was noise

Are there any hints for troubleshooting booting, please?

> Does anyone know what each of the pins on the 6502 CPU chip in the Apple II Plus does?
They all plug into the socket on the motherboard to keep the chip from drifting away. - c.s.a2 FAQ of yore

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Re: New Board Development - SBC6120-RBC Edition [message #5321 is a reply to message #5320]

Sat, 13 October 2018 12:57

Andrew B
Messages: 438
Registered: October 2015
Location: Hawthorne, CA

Senior Member
Administrator

Seems like you might still have some kind of a serial problem?

If you boot without the flash card attached, and type 'h <enter>' at the prompt, do you get the monitor ROM help?

Can you dump RAM, 'e 0000-1000 <enter>'

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Re: New Board Development - SBC6120-RBC Edition [message #5322 is a reply to message #5321]

Sat, 13 October 2018 14:40

will
Messages: 182
Registered: October 2015

Senior Member

I had a problem with keys repeating - they would just repeat until the monitor's input buffer was full. It turned out that the GAL at U11 was not programmed correctly (or it was a faulty chip). I swapped in a newly programmed replacement GAL at U11 and the issue went away.

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Re: New Board Development - SBC6120-RBC Edition [message #5323 is a reply to message #5322]

Sat, 13 October 2018 15:03

Andrew B
Messages: 438
Registered: October 2015
Location: Hawthorne, CA

Senior Member
Administrator

These GALs came from one of my wait list kits, so they were tested to boot & run Adventure off a CF card before being sent out. Not that there couldn't be a problem, but it would be the first I'd heard of with any of the kits or partial kits that I've sent out.

I have found that some of my CF cards are sensitive to the duration of the reset pulse and holding down the reset button for longer makes them come up. But I'd definitely recommend testing without the CF card first to make sure the monitor is running properly. (The monitor is pretty smart, when you ask for help for instance it only shows the IDE commands if there is an IDE drive detected! Wink

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Re: New Board Development - SBC6120-RBC Edition [message #5324 is a reply to message #5323]

Sun, 14 October 2018 01:34

Simmo
Messages: 3
Registered: November 2015
Location: Australia

Junior Member

Yeah, I picked up a D1-6120-9C ($AUD17) and a HD3-6402R-9 ($AUD4.50) from UT Source which look OK. Hopefully they work. Yet to get myself a PCB, which I'll get shortly from Andrew B, and test these chips. Looking forward to a PDP adventure game myself.

Andrew B, let us know through the boardinventory page what you have left available for the SBC6120-RBC.

Thanks,
Simmo

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Re: New Board Development - SBC6120-RBC Edition [message #5325 is a reply to message #5324]

Sun, 14 October 2018 15:07

Andrew B
Messages: 438
Registered: October 2015
Location: Hawthorne, CA

Senior Member
Administrator

So - there have been a few people who have been waiting a long while for 'wait list' stuff. Apologies to the people who have patiently waited. I hate to take any $$ unless I know I can ship promptly, so it's been slow going since I made the giant bath of 65 original kits. I'm ordering some GALs + EEPROMs to get caught up along with more PCBs. I have a few tested 6120s left but based on the wait list I have, I believe that they are all likely spoken for at this point. If I get through the list and any are left, I'll post back here.

The mis-numbered D1-6120 from UTSource seems like a good option right now.

[Updated on: Sun, 14 October 2018 15:07]

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Re: New Board Development - SBC6120-RBC Edition [message #5327 is a reply to message #5321]

Mon, 15 October 2018 09:48

scruss
Messages: 13
Registered: December 2015
Location: Toronto, Canada

Junior Member

Andrew B wrote on Sat, 13 October 2018 15:57

Seems like you might still have some kind of a serial problem?

If you boot without the flash card attached, and type 'h <enter>' at the prompt, do you get the monitor ROM help?

Can you dump RAM, 'e 0000-1000 <enter>'

Can't seem to do either. Entering 'H<cr><lf>' at the prompt usually returns a <lf>. This last time I've tried it, all three POST lights lit up and it seems to have hung.

(I'd be happy to start another thread about this, as my serial issues must be tedious for other readers. Wink

What I've tried/tested:

two different null modem cables
two different serial adapters
continuity between 6402 and MAX232: good
continuity between MAX232 and serial out: good
capacitors on MAX232 are all good
Replacing the MAX232 with a socket and USB serial adapter resulted in all three POST bits lit and no useful function
reset button often doesn't work, even if held for a long time and no CF2IDE adapter present. Usually resets to just power LED and no POST
both oscillators doing their job (or there would be no coherent monitor message)
no obvious bent pins or shorts in the dual-wipe sockets
I have been more careful with ESD precautions with this build than any other, given the dire warnings in the manual
The board was less compatible with my lead-free + no-clean flux soldering setup than I'd hoped
(smallest CF I current have is 512 MB, and written using Etcher; I'm getting smallest cards I could find by mail this week)

Guess I'll have to trace every line and see if something's not connected.

> Does anyone know what each of the pins on the 6502 CPU chip in the Apple II Plus does?
They all plug into the socket on the motherboard to keep the chip from drifting away. - c.s.a2 FAQ of yore

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Re: New Board Development - SBC6120-RBC Edition [message #5336 is a reply to message #5327]

Mon, 15 October 2018 20:02

Andrew B
Messages: 438
Registered: October 2015
Location: Hawthorne, CA

Senior Member
Administrator

It sounds like you're getting to the end of all of the logical things to do.

Did you happen to substitute any of the 7400 series logic with a different series compared to what is in the BOM? We had strange intermittent issues with some 74ACT (I think?) chips on the Rev 0.99 board, but I went to thicker power & GND traces + 2 Oz copper on the Rev 1.xx boards and that seemed to resolve that issue, even the previously problematic chips worked fine.

Where did you source the rest of the chips for the build?

I don't mind if we stay in this thread or split it off, totally up to you.

[Updated on: Mon, 15 October 2018 20:03]

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Re: New Board Development - SBC6120-RBC Edition [message #5343 is a reply to message #5336]

Wed, 17 October 2018 05:37

scruss
Messages: 13
Registered: December 2015
Location: Toronto, Canada

Junior Member

All my logic chips are TI SN74HC... types, bought new from Digikey using your BOM generator, like all the other chips. I did find one dry joint on the low EEPROM, but fixing that made no difference. I may try the simple expedient of taking all the chips out and re-socketing them.

After that, I guess I'll have to test the logic chips one by one.

> Does anyone know what each of the pins on the 6502 CPU chip in the Apple II Plus does?
They all plug into the socket on the motherboard to keep the chip from drifting away. - c.s.a2 FAQ of yore

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Re: New Board Development - SBC6120-RBC Edition [message #5375 is a reply to message #5343]

Sat, 20 October 2018 20:41

scruss
Messages: 13
Registered: December 2015
Location: Toronto, Canada

Junior Member

Reseated the chips ... and I don't even get POST any more ☹
Is there a way to get a nice connection table (basically a text version of the schematic, showing U1 P1 going to ___, U1 P2 going to ___, etc) from kicad? The schematics would be so much page flipping.

> Does anyone know what each of the pins on the 6502 CPU chip in the Apple II Plus does?
They all plug into the socket on the motherboard to keep the chip from drifting away. - c.s.a2 FAQ of yore

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Re: New Board Development - SBC6120-RBC Edition [message #5376 is a reply to message #5375]

Sat, 20 October 2018 20:52

Andrew B
Messages: 438
Registered: October 2015
Location: Hawthorne, CA

Senior Member
Administrator

There should be a text file of the netlist in the .zip with the Gerber & KiCAD files. Take a look at SBC6120-RBC.net, in the bottom of the file all of the nets are listed.

If you want to post or send some pictures of the board, I'll take a look to see if there is anything amiss.

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Re: New Board Development - SBC6120-RBC Edition [message #5388 is a reply to message #5376]

Mon, 22 October 2018 15:00

scruss
Messages: 13
Registered: December 2015
Location: Toronto, Canada

Junior Member

Thanks, Andrew. I managed to generate a sorted by component netlist using kinparse - https://github.com/xesscorp/kinparse .

Photos are here:

I fear I may have burnt off a couple of pads, so as long as there aren't too many I might be able to use patch wires. If not, I may have to come back to you for a new board.

> Does anyone know what each of the pins on the 6502 CPU chip in the Apple II Plus does?
They all plug into the socket on the motherboard to keep the chip from drifting away. - c.s.a2 FAQ of yore

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