Is this also true for electronics design? - Page 1
Forum section: electronics / general

author: station240
author_rank: Unknown
timestamp: May 19, 2016, 03:00:33 pm
content: saucehttps://xkcd.com/844/Some people's circuit diagrams remind me of this onehttps://xkcd.com/1513/

author: PChi
author_rank: Frequent Contributor
timestamp: May 19, 2016, 04:28:10 pm
content: Yes, it's the same for hardware.It's so important to set the requirements / define the specifications before starting work.It's really annoying when you inherit a flawed project. You put effort in to make the heap of crap mostly work (not being allowed to throw the 'work' already done away) then you get the blame for the resultant pile of steaming turd.

author: Carl_Smith
author_rank: Frequent Contributor
timestamp: May 20, 2016, 04:19:09 am
content: You can't bring up XKCD on an electronics forum without mentioning this one:http://xkcd.com/730/

author: dmills
author_rank: Super Contributor
timestamp: May 21, 2016, 09:38:20 pm
content: Quote from: PChi on May 19, 2016, 04:28:10 pmYep, sounds about right. Also, you get landed with fixing the firmware for the steaming pile for ever more.Regards, Dan.

author: Wilksey
author_rank: Super Contributor
timestamp: May 21, 2016, 09:51:40 pm
content: Yes!I have had minor changes to requirements within a software project and although a pain, it's been relatively easy to implement, changes to hardware requirements, when you have already built the board, catastrophic in some cases!I also hate the fact that certain people seem to think that hardware only needs take a few days, and some simple software is acceptable to take 6 months to write! Hardware design is obviously magic and can be done overnight and work first time even the most complex of designs is no problem!

author: lemmegraphdat
author_rank: Frequent Contributor
timestamp: May 21, 2016, 10:35:08 pm
content: So where does this crappy junk end up?

author: Gribo
author_rank: Frequent Contributor
timestamp: May 23, 2016, 08:01:08 pm
content: Walmart.

author: stmdude
author_rank: Frequent Contributor
timestamp: May 23, 2016, 08:05:06 pm
content: Quote from: dmills on May 21, 2016, 09:38:20 pmI thought us software guys got stuck with the steaming pile?

author: hans
author_rank: Super Contributor
timestamp: May 23, 2016, 09:28:23 pm
content: All complex projects will have technical debt. I can understand that sometimes you need to get something out of the door to make money. However rushing things will always be at a cost. Personally I like to see how technical debt on long-term projects are dealed with, it can tell alot how serious a company is about quality > features, how projects are planned and managed.For hardware this is much harder. There will always be some technical debt, but it ought to be a lot smaller. Once the hardware is made and shipped, it should be done. You can't ask a customer to open the machine and solder in a 2.2k 0603 resistor between IC201 pin 7 and IC305 pin 3. Sending a patch cable (if possible at all) costs money, requires updated instruction manuals, testing, etc. So it's absolutely crucial to make up your mind before drawing a schematic, let alone a board. And test it. Can't second guess stuff.Unfortunately I've inherited some electronic projects done by engineers that moved on to sales positions later. That showed in the lack of (functional) I/O protection circuits, lack of adhering to datasheet absolute maximum specifications (especially long-term stuff, fun to track down), discrepancies in schematic/PCB/BOM, no documentation, no version control, etc. When work needed to be done, in most cases my answer was "scrap it and start over".Luckily at that time we had switched from Eagle to Altium Designer, which meant: "you could import Eagle projects into Altium 14.3, but the crapiness of those Eagle project drawings aren't magically fixed. To fix that starting from scratch doesn't take significantly longer".Note that these were only moderately complex PCBs, like 4-6 layers, QFP's and analog bits and pieces.It was still very frustrating. Because I can't change anything significant without a lot of visible consequences. Change pin-out or digital chips of micro? Needs firmware changes to identify between 2 hardware revisions. Change pin-out of connector? Nope, for some boards we had 20 kit cables, that won't happen.

author: dmills
author_rank: Super Contributor
timestamp: May 24, 2016, 01:13:04 am
content: Living very much that at the moment, I hate the one where you can find the schematic but not the layout cad files, and just need to change one footprint on a complex board to resolve an obsolescence issue (WHY is it always inductors or connectors that screw you), very boring (Also the one where the silly bugger has checked in the schematic but NOT THE BLOODY LIBRARY).Then we had the whole £7 won hun lo power supply shipping with a £3,000 box, my suggestion that we replace it with at least something from say Meanwell (Cost £14, but has an electrolytic from someone I have heard of and a three year warranty) caused screaming because of the 100% cost increase (Going to what I really wanted - TDK or the better end of the XP power stuff would have caused heart attacks (£25 or so)).To be fair, properly protecting GPIO is a complete pain in the bum, and I am sure it is not taught in school.Regards, Dan.