MIPI woes, good design ideas and headaches

[Exophase]

As someone who has designed many boards, I have never found JTAG to be practical for board testing.

For programming FPGAs and debugging microprocessors, it is fine, but you seldom use more than one FPGA per design. Usually you end up with a separate JTAG port for each device that supports JTAG because daisy chaining the JTAG through multiple devices from different manufacturers complicates FPGA programming and microprocessor debugging.

Also quite often most of the ICs on the board don't support JTAG, so JTAG testing would only get partial coverage.

I've almost never used JTAG for debugging or interfacing with microcontrollers either, even when using zero OS code. The FPGA guys at work haven't been using JTAG either.

 

[DAP]

As someone who has designed many boards, I have never found JTAG to be practical for board testing.

For programming FPGAs and debugging microprocessors, it is fine, but you seldom use more than one FPGA per design. Usually you end up with a separate JTAG port for each device that supports JTAG because daisy chaining the JTAG through multiple devices from different manufacturers complicates FPGA programming and microprocessor debugging.

Also quite often most of the ICs on the board don't support JTAG, so JTAG testing would only get partial coverage.

If you consider that ED will receive the same amount of boards he has as with the pandora (I hope it will be less, as the old boards had more problems than the new ones) you would still say it is a feature he shouldn't have on the board?

I don't design boards for work myself, but the PCBs that had to be checked were done faster by running the boundary scan test than writing a self-test firmware. From scratch the tool could check the PCBs CPU/FPGA in less than 5 minutes (incl. searching for the bsdl).

With a bit more effort I could check flash, RAM and the daughter-board. Some parts you can't test as they are out of your net, but that depends mostly on the design you've made.

Also the MIPI standard that is used can be accessible from the SD-Card slot (if it has been designed to do so on the PCB), you can debug from there also.

But I can't tell if it will take ++hours to design the PCB to work with those standards, it should stay cost effective in the end.

If we want to go in depth it might be wise to open a different topic about this.

To test with JTAG, both ends of each connection to be tested must be JTAG devices, and both be in the same JTAG chain.

Realistically it is likely that only one device in the Pyra, the SOC will have JTAG which means the JTAG can test exactly nothing. At this point, as with most boards, the JTAG becomes useful for debugging code in the SOC, and nothing else.

 

[Natsu]

I know it's random and early for that, but I think you should do Indiegogo with

Flexible Funding.

 

[TrashyMG]

I deal with boundary scan on the wafer die level in test programs I generate at work.. Although we have proprietary names for our several different methods of achieving a Bountry Scan like test.  

Edit: Also nothing is every as easy as just hitting a button and seeing a green light.. We need to check every latch on that die, but need a method of getting at and testing specific IP that isn't  accessible on I/Os pins available. Some times it takes day(s)/week(s) worth of processing on the fastest machine we have available to generate patterns for it to do a decent functionality test.

 

[TeDaDeS]

I deal with boundary scan on the wafer die level in test programs I generate at work.. Although we have proprietary names for our several different methods of achieving a Bountry Scan like test.  

Edit: Also nothing is every as easy as just hitting a button and seeing a green light.. We need to check every latch on that die, but need a method of getting at and testing specific IP that isn't  accessible on I/Os pins available. Some times it takes day(s)/week(s) worth of processing on the fastest machine we have available to generate patterns for it to do a decent functionality test.

The only part I now that really is pressing a button and getting a green light is the tjag-live tool, you select your bsdl's and put them in order them in the chain they are on the board. Press the start button and it will do the rest.

If you want to do more you can, but you'll be using the netlist etc. and probably manually configuring tests. The implementation is the same, but if it is not accessible on the PCB you couldn't do it anyways, even though there are people around that could set-up the rest.

And as far as the MIPI debugging goes, it takes the SD-Card pins not the actual SD-Card so you don't have to put extra testing ports on the final board.

The test application on the SD-Card is when the device is final, most of the stuff is probably working already. JTAG could be used on the prototype also and when final boards don't appear to be doing anything.

But if people agree it is to much hassle for the development of the pyra we shouldn't add it I guess.

 

[cuetzpalin]

I know it's random and early for that, but I think you should do Indiegogo with


Flexible Funding.

I have the impression that Kickstarter helps to gain more visibility. The thing would be to set a reasonable goal we are sure to meet.


If there's a Kickstarter/Indiegogo and an alternative to preorder directly... which would most people here choose?


Does anybody here knows which fees are lower? (Between KS and Indiegogo)

 

[TeDaDeS]

I know it's random and early for that, but I think you should do Indiegogo with


Flexible Funding.

I have the impression that Kickstarter helps to gain more visibility. The thing would be to set a reasonable goal we are sure to meet.


If there's a Kickstarter/Indiegogo and an alternative to preorder directly... which would most people here choose?


Does anybody here knows which fees are lower? (Between KS and Indiegogo)

If I remember correctly KS has 10% fee (5% fee + 5% creditcard fee), Indiegogo has 9% fee but you will get 5% back if you reach your goal (so guessing Pyra would do great, it would cost 4% fee).

Thinking the Pyra would do good anyways, the Kickstarter campaign would only serve as great publicity.

 

[Klumpen]

You know if we're going to refer to them as face buttons maybe we should label them with smileys instead of letters.    it would nicely solve the problem of which letter should go with which button

- Neelix

This is actually a nice idea

Press Happy Button to start fun times!

Press Angry button to shoot the incoming alien threat!

Press the Sad button to exit the game.

I like this idea very much, would be something new and make awesome game instruction texts.

New button Layout:

          o.Ò  

>:]       :-/    >.<

      :-D

This could be used in a pyra exclusive game that's based on the emotions of the character, like "Eeets!" or "Super Princess Peach" (actually good games).

 

[Klumpen]

The LEDs in the front row will be multicolor as will a special surprise LED.

Oh, maybe an indicator for a surprise function.

"Another Pyra detected in your area - engaging battle mode"

 

[comradekingu]

http://www.ti.com/lit/ds/symlink/omap5432.pdf#page=77&zoom=auto,0,720

2.4.6.5 MIPI NIDnT (Narrow Interface for Debug and Test)
Typically, the device wide debug port is not available on a packaged end product phone due to
connectivity and footprint constraints.
The OMAP5432 provides a narrow debug interface on SD Card connector compliant to the MIPI NIDnT
specification. The MIPI NIDnT functionality is supported with full software control.
Table 2-33
provides the NIDnT signal descriptions

Gary cooper from TI works at http://www.mipi.org/working-groups/debug

 

[ssokolow]

You know if we're going to refer to them as face buttons maybe we should label them with smileys instead of letters.    it would nicely solve the problem of which letter should go with which button

- Neelix

This is actually a nice idea

Press Happy Button to start fun times!

Press Angry button to shoot the incoming alien threat!

Press the Sad button to exit the game.

I like this idea very much, would be something new and make awesome game instruction texts.

New button Layout:

          o.Ò  

>:]       :-/    >.<

      :-D

This could be used in a pyra exclusive game that's based on the emotions of the character, like "Eeets!" or "Super Princess Peach" (actually good games).

My main problems with using symbolic buttons are that they're more awkward to write about and they're also counter-standard.

Which would you rather type or say? "Hold Select and Press XXYBA" (NES/SNES/N64/GC/Wii/GB/GBC/GBA/DS/Genesis/Saturn/DC/X-Box/360/XBone/etc., One Syllable Each) or "Hold Select and Press Triangle, Triangle, Square, X, Circle" (PSX/PS2/PS3/PS4, Three Syllables each)?

Yeah, it doesn't help that that the de facto standard PC gamepad (X-Box 360 controller) needlessly mirrored the Nintendo layout, putting muscle memory at odds with accurate in-game labelling, but I still prefer letters. (Ever notice that? All Nintendo controllers walk the alphabet from right-to-left while 360 controllers use a mirrored form of the SNES layout's buttons.)

 

[Neelix]

One of the biggest issues I had with the Pandora when talking about pressing keys was the need to qualify which A, B, X or Y key I meant, as the Pandora has 2 of each.  It would actually simplify things greatly to use symbols instead of letters to refer to those keys. (symbols that are easily named but don't otherwise appear anywhere else on the keyboard, so that there is no room for confusion)

To be honest I don't see how the number of syllables in the name of the key has any relevance at all.

- Neelix
 

 

[hns]

I know it's random and early for that, but I think you should do Indiegogo with

Flexible Funding.

I have the impression that Kickstarter helps to gain more visibility. The thing would be to set a reasonable goal we are sure to meet.

If there's a Kickstarter/Indiegogo and an alternative to preorder directly... which would most people here choose?

Why should people have to choose? It is possible to run all types of campaigns in parallel to get the best visibility...

 

[comradekingu]

http://selfstarter.us/ seems like a viable platform, doesnt cost anything, and you do the work yourself. No imposed rules from either kickstarter or indiegogo, or any of the others.

 

[ShleeDragon]

http://selfstarter.us/ seems like a viable platform, doesnt cost anything, and you do the work yourself. No imposed rules from either kickstarter or indiegogo, or any of the others.

http://www.crowdhoster.com/ is backed by crowdtilt..... and that's an excellent platform too

 

[Natsu]

I was going for initial start up/pre-orders. Honestly running all of those would be confusing. Kickstarter seem like the most risky while the others are less known. Indiegogo (with Flexible Funding) is right in the middle.

 

[Klumpen]

My main problems with using symbolic buttons are that they're more awkward to write about and they're also counter-standard.

Which would you rather type or say? "Hold Select and Press XXYBA" (NES/SNES/N64/GC/Wii/GB/GBC/GBA/DS/Genesis/Saturn/DC/X-Box/360/XBone/etc., One Syllable Each) or "Hold Select and Press Triangle, Triangle, Square, X, Circle" (PSX/PS2/PS3/PS4, Three Syllables each)?

Yeah, it doesn't help that that the de facto standard PC gamepad (X-Box 360 controller) needlessly mirrored the Nintendo layout, putting muscle memory at odds with accurate in-game labelling, but I still prefer letters. (Ever notice that? All Nintendo controllers walk the alphabet from right-to-left while 360 controllers use a mirrored form of the SNES layout's buttons.)

The problem I got with every controller but my Saitek is, that XYAB are somewhere else every time, the SNES X (Up) is in a different place than the GameCube X (right), the Xbox X (left), or the Playstation X and the Pandora X (down) for example. Saitek made it easy und just numbered the buttons in the exact order that they are recognized via standard USB drivers.

I would go with Numbers or Symbols than can be written and understood easily , for example:

          o.Ò

>:]       :-/    >.<

      :-D

=       Mock      Won(der)

Mean        Meh    Ann(oyed)

        Happy

------------------------------------

           Saitek p2600

7                                      8

5                                      6

                         4     light

                     1      3   dark

                         2

5-8 are shoulders. I'd use 5 and 6 for the right ones which aren't labeled but recognized as 9 and 10 by software.

A numeric system is good because it can always be referred to as "B1", "B2", etc... although the emoticons have a more special appeal.

@Kickstarter sidethread: Not possible in Germany and not possible to pay there in Europe + they got hacked a few days ago.

http://boards.openpandora.org/topic/15693-kickstarter-hacked-user-data-stolen/

 

[Foxgod]

Personally i do think that weird symbols will make the pyra look a bit cheap

 

[Natsu]

lol I Hope you aren't serious with those symbols.

It would be best to leave the 6 buttons blank.

 

[Neelix]

lol I Hope you aren't serious with those symbols.


It would be best to leave the 6 buttons blank.

Blank?  I think not. That would be even worse than the current situation with the Pandora - there'd be no easy way to indicate which button to press at all! 

While I wouldn't use text based emoticons for the symbols,  I can see a case for using the graphical equivalents.  That being said, I'd be happy with any other selection of easily named symbols that aren't used elsewhere on the keyboard.

- Neelix