Two buttons labelled "forwards" and "backwards" would be excellent if it was light enough to read the labels. But slide projectors are usually operated in a darkened room and, as I have discovered to my embarrassment, it is very easy to confuse the two buttons. You could label them in Braille I suppose but that, for all but the registered blind, would be as counter-intuitive as the single button so;ition. On 18 July 2014 19:58, Vitaliy M wrote: > It takes an engineer to argue that a single button projector interface is > "reasonable". 'Cause, you know, a two-button interface (back/forward) is > unnecessary luxury. :) > > "The concept of an intuitive user interface is deeply flawed". Not really= .. > Few men would be baffled by two buttons labeled "forward" and "back". On > the other hand, there are documented cases of people baffled by the > "clever" single-button UI. > > > And a designer who thinks his > > interface is intuitive also thinks that that spareshim the necessity of > > documenting it. > > Non-sequitur, but I'll bite. I've never read my iPhone manual. But every > time I go to use my air-air handheld, I am convinced that the guys who > designed the UI, were guided by the motto "Screw intuitive UI, RTFM". > > Sent from my phone > > > On Jul 18, 2014, at 11:30, David C Brown wrote: > > > > Panel space is the main limitation, along with the number of inputs to > the > > PIC. O remember that slide projector interface used to be common and > > rarely caused problems. It is not unreasonable to expect users to have > > some familiarity with the equipment that they are using. The concept = of > > an intuitive user interface is deeply flawed since what is intuitive to > one > > man is deeply baffling to another. And a designer who thinks his > > interface is intuitive also thinks that that spareshim the necessity of > > documenting it. /rant > > > > > >> On 18 July 2014 19:01, Vitaliy M wrote: > >> > >> Why is "minimum panel hardware", important for this project? Cost, siz= e > >> limitations, ... ? > >> > >> A note of caution: engineers are known for being proud of clever > >> solutions, at the expense of usability. > >> > >> In one of the books on UI design, the author cites an example of a sli= de > >> projector, where a single button was used to control the slide show. > Click > >> once to advance to the next slide. Hold the button for one second, to = go > >> back. Genius! Except when an unfamiliar user is asked to run the > projector, > >> and the slides start to jump back and forth. The engineer shaved $0.10 > off > >> a $200 BOM, whoop-dee-doo. > >> > >> If it's a one-off device, for your use, cost of the UI shouldn't be an > >> issue. If it's something you're expecting to ship in volume, I would t= ry > >> hard to make the UI as intuitive as practical. > >> > >> Sent from my phone > >> > >>> On Jul 18, 2014, at 6:17, David C Brown wrote: > >>> > >>> I am building a simple pulse generator using an LTC6903 "synthesiser > >> chip" > >>> and a few TTL chips. The range will be from about 0.1Hz to 68MHz and > the > >>> frequency is set, geometrically, by a 15 bit control word. I will b= e > >>> using a PIC16F87 to control the synthesiser and drive a display. > >>> > >>> My problem is how to set the frequency by hand using the minimum pan= el > >>> hardware. I need control at the finest level, stepping the control > >>> register by one but also need to be able to make large frequency shif= ts > >>> quickly, perhaps stepping the register by 2^10 > >>> > >>> I have studied this for some time and come up with several solutions, > non > >>> of them entirely satisfactory, but I would appreciate, in the first > >>> instance, suggestions which are not influenced by my thinking. > >>> -- > >>> __________________________________________ > >>> David C Brown > >>> 43 Bings Road > >>> Whaley Bridge > >>> High Peak Phone: 01663 733236 > >>> Derbyshire eMail: dcb.home@gmail.com > >>> SK23 7ND web: www.bings-knowle.co.uk/dcb > >>> > >>> -- > >>> http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive > >>> View/change your membership options at > >>> http://mailman.mit.edu/mailman/listinfo/piclist > >> > >> -- > >> http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive > >> View/change your membership options at > >> http://mailman.mit.edu/mailman/listinfo/piclist > >> > > > > > > > > -- > > __________________________________________ > > David C Brown > > 43 Bings Road > > Whaley Bridge > > High Peak Phone: 01663 733236 > > Derbyshire eMail: dcb.home@gmail.com > > SK23 7ND web: www.bings-knowle.co.uk/dcb > > > > -- > > http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive > > View/change your membership options at > > http://mailman.mit.edu/mailman/listinfo/piclist > > -- > http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist > --=20 __________________________________________ David C Brown 43 Bings Road Whaley Bridge High Peak Phone: 01663 733236 Derbyshire eMail: dcb.home@gmail.com SK23 7ND web: www.bings-knowle.co.uk/dcb --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .