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ECB-4PIO-R03 [message #5181] Fri, 14 September 2018 22:05 Go to next message
b1ackmai1er is currently offline  b1ackmai1er
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Hi Gents,

I have manufactured board for and built an ECB-4PIO board.

On power on, the PIO chips have popped. After checking the GND and VCC pins of the PIO it appears they are connected to the wrong power lines on the circuit board. The board appears to have been designed wrong as the circuit diagram appears right.

Has anyone else build one of these boards?



Regards Phil.
Re: ECB-4PIO-R03 [message #5182 is a reply to message #5181] Sat, 15 September 2018 11:50 Go to previous messageGo to next message
norwestrzh is currently offline  norwestrzh
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Phil writes:

>> On power on, the PIO chips have popped. After checking the GND and VCC pins of the PIO it appears they are connected to the
>> wrong power lines on the circuit board. The board appears to have been designed wrong as the circuit diagram appears right.

>> Has anyone else build one of these boards?

I have not built one of these, but recently I used KiCAD to layout a fairly complex board (68k SBC with all TTL "glue logic"), and discovered that, in spite of a clear connection in the schematic to Vcc for the common pin of a pull-up SIP, there was no such connection on the PCB layout. I can't decide if the problem is with KiCAD, OR the so-called "free router" that I used to route the board. IMO, this is a terrible development for people who are trying to use these tools for PCB work.

Anybody else seeing things like this? Does this mean that anybody who wants to create PCBs must purchase the VERY expensive Eagle software?

Roger
Re: ECB-4PIO-R03 [message #5183 is a reply to message #5181] Sat, 15 September 2018 12:13 Go to previous messageGo to next message
Andrew B is currently offline  Andrew B
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Quote:
Has anyone else build one of these boards?


You might search back through the legacy mailing list archive, but I don't think there is any discussion on it since we moved forums.

Quote:
I have not built one of these, but recently I used KiCAD to layout a fairly complex board (68k SBC with all TTL "glue logic"), and discovered that, in spite of a clear connection in the schematic to Vcc for the common pin of a pull-up SIP, there was no such connection on the PCB layout. I can't decide if the problem is with KiCAD, OR the so-called "free router" that I used to route the board. IMO, this is a terrible development for people who are trying to use these tools for PCB work.


We don't even know if freerouter was used for the ECB-4PIO-R03 board, or maybe if it was hand routed....

This is very likely a schematic-related netlist mistake.

I ran into this when I did the SBC6120-RBC Edition - I needed a global label so the netlist would cross pages, and I put a local label instead by mistake. So I ended up with two nets that weren't connected. The schematic is just a way to create the netlist, so it's worthwhile to scan the netlist make sure that there is nothing weird going on before you send it over to freerouter.

If your netlist is correct, freerouter should be a reliable tool, lots of people use it.




Re: ECB-4PIO-R03 [message #5184 is a reply to message #5182] Sat, 15 September 2018 12:30 Go to previous messageGo to next message
wsm is currently offline  wsm
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Quote:
Does this mean that anybody who wants to create PCBs must purchase the VERY expensive Eagle software?

I've been using an older standalone version of Eagle for many years and they've been playing with the pricing options for the last couple of years. First they introduced "cloud" versions in addition to purchased versions. When Autodesk bought it they went to a subscription model ... something I *HATE* because new features can force old designs to require updates or if a company pulls a product you're left with no way to update older designs.

The one benefit of the subscription model I might use is for a two layer board that I've considered upgrading to four layers. It would be easy to add the power / ground vias in my two layer version and then pay $15 for one month while I cleaned up the layout in four layers and generate gerbers.

I just looked at the Autodesk website and it looks like they've again changed the pricing options back to a FREE option for small boards (2 layers, 80 sq. cm / 12.4 sq. in) or a yearly fee for the bigger versions: i.e. $100/yr for 4 layers, 160 sq. cm / 24.8 sq. in. It also appears they still have the subscription option but it's not as obvious.
Re: ECB-4PIO-R03 [message #5185 is a reply to message #5183] Sat, 15 September 2018 13:17 Go to previous messageGo to next message
jcoffman is currently offline  jcoffman
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KICAD is generally very good; but be sure VCC and GND are declared to be "power pins" in the parts library. The signal name for +5v MUST be VCC. The signal name for ground MUST be GND. And these signals MUST have "PWR_FLG" part outlines connected to them at some point in the schematic.

Use wide (26-32 mil) traces on VCC and GND. 4-layer boards may use VCC & GND planes.

Freeroute handles Kicad output well, in my experience.

And in the end: check, check, check. The errors I have experienced were usually traced back to cockpit errors. KICAD/Freeroute are complex programs with many options, especially the former.

Signal errors are easy to fix with a wire; VCC and GND errors can be an order of magnitude more difficult to correct.

--John





Re: ECB-4PIO-R03 [message #5186 is a reply to message #5185] Sat, 15 September 2018 19:52 Go to previous messageGo to next message
b1ackmai1er is currently offline  b1ackmai1er
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HI guys,

Thanks for all the feedback.

Unfortunately the original kicad files are no longer available.

I guess what surprises me is that this is R03 of the board, so it worked previously. I suspect when during the changes from R02 to R03 something went wrong with the netlist or labelling. Maybe nobody has actually made a R03 board before.

I am working through the required changes to the board at the moment and will post an errata.

Regards Phil.


Re: ECB-4PIO-R03 [message #5187 is a reply to message #5186] Sat, 15 September 2018 19:54 Go to previous messageGo to next message
Andrew B is currently offline  Andrew B
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Yeah I'm working on tracing it back right now. It looks R02 was probably correct, and something got messed up in R03. It's likely that no one ever made an R03 board. Sad
Re: ECB-4PIO-R03 [message #5222 is a reply to message #5187] Tue, 25 September 2018 06:43 Go to previous messageGo to next message
b1ackmai1er is currently offline  b1ackmai1er
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Hi Gents,

I have posted an errata on the wiki site.

https://www.retrobrewcomputers.org/doku.php?id=boards:ecb:4p io:errata

Any feedback on this would be appreciated.

Regards Phil.
Re: ECB-4PIO-R03 [message #5251 is a reply to message #5185] Sun, 30 September 2018 14:27 Go to previous messageGo to next message
norwestrzh is currently offline  norwestrzh
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Hi John --

Thanks for the tips!

>> KICAD is generally very good; but be sure VCC and GND are declared to be "power pins" in the parts library.

Would you be more specific about this? I'm not sure what you mean.

>> The signal name for +5v MUST be VCC. The signal name for ground MUST be GND.

Yep, did that.

>> And these signals MUST have "PWR_FLG" part outlines connected to them at some point in the schematic.

Just once then? On each sheet? I've tried to do this in the past and had the connectivity checker complain about it. Had to remove the power flag in order to get a clean check.

>> Use wide (26-32 mil) traces on VCC and GND.

Yes, I always use wider traces for VCC and GND -- not sure how wide however (I think about 2x signal traces).

>> And in the end: check, check, check. The errors I have experienced were usually traced back to cockpit errors.

I've had lots of cockpit errors! *grin* In this case, however, KICAD (or Freeroute?Wink completely ignored a connection of VCC to pin 1 of a pull-up SIP. I checked the schematic carefully to be sure that the connection was actually there, and it was. No matter how carefully I check over a board layout, I doubt that I'd catch something like this. I just never expected it to be a problem.

>> Signal errors are easy to fix with a wire; VCC and GND errors can be an order of magnitude more difficult to correct.

Yes, this was easy to fix, but quite annoying. It was a shock to me because the wiring was clearly there in the schematic.

Roger
Re: ECB-4PIO-R03 [message #5258 is a reply to message #5251] Mon, 01 October 2018 07:35 Go to previous messageGo to next message
jcoffman is currently offline  jcoffman
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norwestrzh wrote on Sun, 30 September 2018 14:27
Hi John --

Thanks for the tips!

>> KICAD is generally very good; but be sure VCC and GND are declared to be "power pins" in the parts library.

Would you be more specific about this? I'm not sure what you mean.
ANS: From EEschema bring up the parts library editor or viewer. Each pin on a part outline has a declaration associated with it; e.g., input, output, tri-state, bidirectional, power input, power output. Pins VCC & GND must be designated "power input". On parts such as 74LS00, the VCC and GND must also be marked as applying to all outlines in the package. I don't know about the latest release of the Kicad library, but as of 5 years ago there were innumerable errors in many parts in the library.

>> The signal name for +5v MUST be VCC. The signal name for ground MUST be GND.

Yep, did that.

>> And these signals MUST have "PWR_FLG" part outlines connected to them at some point in the schematic.

Just once then? On each sheet? I've tried to do this in the past and had the connectivity checker complain about it. Had to remove the power flag in order to get a clean check.
ANS: Yes, just once, no matter how many pages a schematic uses.

>> Use wide (26-32 mil) traces on VCC and GND.

Yes, I always use wider traces for VCC and GND -- not sure how wide however (I think about 2x signal traces).
ANS: The size I use depends upon whether I want the VCC/GND traces to fit between part pads.

>> And in the end: check, check, check. The errors I have experienced were usually traced back to cockpit errors.

I've had lots of cockpit errors! *grin* In this case, however, KICAD (or Freeroute?Wink completely ignored a connection of VCC to pin 1 of a pull-up SIP. I checked the schematic carefully to be sure that the connection was actually there, and it was. No matter how carefully I check over a board layout, I doubt that I'd catch something like this. I just never expected it to be a problem.
ANS: Depending upon what SIP part you used, there is no standard connection to pin 1. Not all SIP's are bussed, so pin 1 will specifically have to have the VCC connection specifically made. Did you use the VCC symbol -- little circle with a line. And the GND symbol is, among others, a little triangle with a line coming out the top.

--John


Re: ECB-4PIO-R03 [message #5260 is a reply to message #5258] Mon, 01 October 2018 09:38 Go to previous messageGo to next message
norwestrzh is currently offline  norwestrzh
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I've had lots of cockpit errors! *grin* In this case, however, KICAD (or Freeroute) completely ignored a connection of VCC to pin 1 of a pull-up SIP. I checked the schematic carefully to be sure that the connection was actually there, and it was. No matter how carefully I check over a board layout, I doubt that I'd catch something like this. I just never expected it to be a problem.
ANS: Depending upon what SIP part you used, there is no standard connection to pin 1. Not all SIP's are bussed, so pin 1 will specifically have to have the VCC connection specifically made. Did you use the VCC symbol -- little circle with a line. And the GND symbol is, among others, a little triangle with a line coming out the top.

--John

Yes, I did a specific connection of VCC to pin 1 of the SIP. KiCAD (or something) completely ignored it. The only thing I *didn't* do is use the power flag on the power connections.

Roger
Re: ECB-4PIO-R03 [message #5261 is a reply to message #5260] Mon, 01 October 2018 14:34 Go to previous messageGo to next message
jcoffman is currently offline  jcoffman
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norwestrzh wrote on Mon, 01 October 2018 09:38


Yes, I did a specific connection of VCC to pin 1 of the SIP. KiCAD (or something) completely ignored it. The only thing I *didn't* do is use the power flag on the power connections.

Roger


What version of Kicad are you using? Windoze or Linux?
I am using the Ubuntu build of Kicad 4.0.7 -- plus a number of personal libraries from earlier versions. The private libraries update parts that contained errors back in that older version (2?, 3?Wink. These libraries are ALWAYS searched before any of the new version 4 libraries. I do know that there is no fooling around with VCC or GND in these libraries. They contain parts such as 74xxx which had errors on the in/out status of pins, and contain parts for specific projects; e.g., MC68030, 72-pin SIMM DRAMs, i80386EX pqfp.

--John
Re: ECB-4PIO-R03 [message #5268 is a reply to message #5261] Tue, 02 October 2018 10:14 Go to previous messageGo to next message
norwestrzh is currently offline  norwestrzh
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>> What version of Kicad are you using? Windoze or Linux?

SuSE Linux and ver. 4.0.4 of KiCAD.

I've never looked at the details of the parts libraries very carefully. I guess I need to start?

Roger



Re: ECB-4PIO-R03 [message #5319 is a reply to message #5222] Sat, 13 October 2018 09:32 Go to previous messageGo to next message
b1ackmai1er is currently offline  b1ackmai1er
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Hi Guys,

Just confirming that the errata seems to resolve the problem.

I have uploaded an additional PIO test program that scans through all the PIO ports and toggles all the lines for testing purposes.

Have not been able to get in contact with Wolfgang.

Regards Phil.

b1ackmai1er wrote on Tue, 25 September 2018 06:43
Hi Gents,

I have posted an errata on the wiki site.

https://www.retrobrewcomputers.org/doku.php?id=boards:ecb:4p io:errata

Any feedback on this would be appreciated.

Regards Phil.

[Updated on: Sat, 13 October 2018 09:33]

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Re: ECB-4PIO-R03 [message #5344 is a reply to message #5319] Wed, 17 October 2018 07:38 Go to previous messageGo to next message
b1ackmai1er is currently offline  b1ackmai1er
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Hi Guys,

This board has been challenging !!!

The address mapping of each pio in the wiki is described as:
PORTBASE+0 DATA CHANNEL A
PORTBASE+1 DATA CHANNEL B
PORTBASE+2 CONTROL CHANNEL A
PORTBASE+3 CONTROL CHANNEL B


But I couldn't get my software to work in this configuration.

This is what seems to work:

PORTBASE+0 DATA CHANNEL A
PORTBASE+1 CONTROL CHANNEL A
PORTBASE+2 DATA CHANNEL B
PORTBASE+3 CONTROL CHANNEL B


Is anyone able to confirm from the schematics?

Thank you.
Re: ECB-4PIO-R03 [message #5351 is a reply to message #5181] Fri, 19 October 2018 05:51 Go to previous messageGo to next message
b1ackmai1er is currently offline  b1ackmai1er
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Hi Guys, In an effort to resolve my own problem I have checked the PIO manual against the schematic and indeed my findings regarding the port mapping appears correct and the wiki description appears wrong. I also checked the zilog-peripherals board and the circuit arrangement is the same and the wiki description of the port arrangement does not match.

It seems unusual to me that both could be wrong - is there something I am missing? I will update the wiki to reflect the correct port mapping unless anyone can identify where I have gone wrong.

index.php?t=getfile&id=1090&private=0

Regards Phil.
  • Attachment: 4pioports.png
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Re: ECB-4PIO-R03 [message #5359 is a reply to message #5351] Fri, 19 October 2018 07:42 Go to previous messageGo to next message
Andrew B is currently offline  Andrew B
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If the physical board matches the schematic, it should work the way the wiki page currently describes. With A0 is connected to PORTSEL (A/B), then the A/B will change with every increment of 1, and the control/data selection will change when A1 changes. So you should get:

PORTBASE+0 DATA CHANNEL A
PORTBASE+1 DATA CHANNEL B
PORTBASE+2 CONTROL CHANNEL A
PORTBASE+3 CONTROL CHANNEL B

Re: ECB-4PIO-R03 [message #5363 is a reply to message #5359] Fri, 19 October 2018 22:24 Go to previous messageGo to next message
b1ackmai1er is currently offline  b1ackmai1er
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Hi Andrew,

Thank you, I can see where I have gone wrong with the interpretation now (doh!Wink

YES! The circuit board is wrong!

PIO PORTSEL AB0 Pin 6 is connected to AB0(A0) pin 18 of the 74LS541 line on the circuit diagram.
PIO CONTSEL AB1 Pin 5 is connected to AB1(A0) pin 17 of the 74LS541 line on the circuit diagram.

On the PCB the PIO pin 6 is connected to pin 17 of the 74LS541 and pin 5 connected to pin 18.

So this is non standard and should be considered an error and should be noted as an errata?

Re: ECB-4PIO-R03 [message #5370 is a reply to message #5363] Sat, 20 October 2018 07:17 Go to previous messageGo to next message
Andrew B is currently offline  Andrew B
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Yeah, that's an error. The copied over from the old wiki portion of the page even mentions that it was supposed to be corrected in the new rev.
Re: ECB-4PIO-R03 [message #5609 is a reply to message #5370] Mon, 26 November 2018 06:37 Go to previous messageGo to next message
b1ackmai1er is currently offline  b1ackmai1er
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Errata updated: https://www.retrobrewcomputers.org/doku.php?id=boards:ecb:4p io:errata
Re: ECB-4PIO-R03 [message #5817 is a reply to message #5609] Fri, 04 January 2019 17:03 Go to previous message
b1ackmai1er is currently offline  b1ackmai1er
Messages: 168
Registered: November 2017
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Hi Guys,

I am doing some work to generate a new PCB for this board with Kicad 5.

I don't have much experience with Kicad and was hoping someone could assist with recommending component footprints for the following to ensure that they suit typical/common components that builders have access to.

My current selection is:

Standard .1uF bypass capacitors:Capacitor_THT_Disc_D7.0mm_W2.5mm_P5.00mm
Standard .25w pullup resistors:Resistor_THT:R_Axial_DIN0204_L3.6mm_D1.6mm_P7.62mm _Horizontal
100uF electrolytic capacitors: Capacitor_THT:CP_Radial_D5.0mm_P2.5mm

https://www.retrobrewcomputers.org/lib/exe/fetch.php?media=b oards:ecb:4pio:r04:ecb-4pio-5jan2019.png

https://www.retrobrewcomputers.org/lib/exe/fetch.php?media=b oards:ecb:4pio:r04:ecb-4pio.zip

Thanks.

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