[HN Gopher] Mysteries of the Griffin iMate and the Apple Extende...
       ___________________________________________________________________
        
       Mysteries of the Griffin iMate and the Apple Extended Keyboard II
        
       Author : fanf2
       Score  : 51 points
       Date   : 2024-08-05 11:42 UTC (3 days ago)
        
 (HTM) web link (www.projectgus.com)
 (TXT) w3m dump (www.projectgus.com)
        
       | lbourdages wrote:
       | Is this weird USB boot signal thing the reason why Apple
       | keyboards used to ship with nonstandard USB connectors that would
       | fit their nonstandard USB extension cord? That would explain it,
       | I have been wondering for years...
        
         | mrpippy wrote:
         | I think that was because the max cable length in the USB 1.0
         | spec is 3 meters.
         | 
         | The fairly short captive keyboard cable plus extension was in
         | spec, but using the extension with anything else likely
         | wouldn't be. Hence, the weird connector to prevent you from
         | using it to extend something else (particularly something with
         | higher current draw)
        
       | playa1 wrote:
       | Excellent article. Very well presented with just the right level
       | of detail and drama.
       | 
       | I had no intention of learning about ADB or crazy Apple USB
       | power-on hacks but here I am having had a great time while doing
       | just that.
       | 
       | 10/10 would recommend and now this blog is on my reading list.
        
       | dotancohen wrote:
       | If you like those keyboards for the keys - and those Alps are the
       | reason that those keyboards are still desirable today - then you
       | might want to check out Matias. They have a terrific Alps clone.
       | It feels amazing, and honestly the split Matias Pro has the best
       | layout I've ever used.
       | 
       | That said, the quality is junk. Each $250 keyboard lasted me one
       | year, no longer. That said, even with the high price and low
       | service life, the Matias Pro is so much more comfortable than any
       | other keyboard that I still consider it a good value for the
       | money.
        
       | worstspotgain wrote:
       | Fun read. One detail towards the end:
       | 
       | > Worse, I'm already kind of dissatisfied with the iMate - it
       | doesn't distinguish left and right for Alt/Shift/etc.
       | 
       | IIRC, the keys were indistinguishable at the ADB hardware level.
       | The iMate is probably not at fault.
       | 
       | Again IIRC, there was also a hard limit of either one or two
       | regular keys held down at one time, plus any combination of
       | modifier keys. Maybe the limit was one key for pre-ADB and two
       | keys for ADB?
        
         | bpye wrote:
         | You can distinguish left and right for alt, shift and control,
         | but not for meta.
         | 
         | I actually built a (rather hacky) ADB-USB for this exact
         | keyboard, you can see the look up table I used for translating
         | scan codes [0].
         | 
         | You only get at most two key events at a time, but you can have
         | more keys held - you'll just receive the events sequentially. I
         | found that the limit depended on which specific keys were being
         | held, but it was certainly more than two.
         | 
         | [0] -
         | https://github.com/benpye/rtos/blob/7971ab6a2f26269223f97b8f...
        
           | worstspotgain wrote:
           | More than two even after excluding the modifier keys
           | (shift/control/option/command)?
        
             | bpye wrote:
             | Just checked, in some cases I guess it is two. For example
             | you can only have two of I, O and P - but you can also have
             | say W, A, S, D and F held. I assume it's a consequence of
             | the key matrix.
        
               | worstspotgain wrote:
               | Roger, thanks for checking. I remember that limit as what
               | Apple advertised for development, but I never actually
               | tested it myself. Maybe Apple reduced it to two at the
               | driver level for consistency too, who knows.
        
       | rgovostes wrote:
       | (2023) Previously: https://news.ycombinator.com/item?id=35772131
        
       | qwerty456127 wrote:
       | > or pick a real challenge like bit-banging low speed USB in Rust
       | on a dirt cheap RISC-V micro
       | 
       | A USB so slow it can't even handle a keyboard smoothly?
        
       | Reason077 wrote:
       | > _"My local $2 shop didn 't have a CR1225 cell, but they did
       | have a CR1220 cell which is the same thickness and voltage."_
       | 
       | A CR1220 cell is by definition _not_ the same thickness as a
       | 1225.
       | 
       | - CR = Lithium cell, round 12 = 12mm diameter 25 = 2.5mm
       | thickness
       | 
       | With only 0.5mm difference in thickness, they will be
       | interchangeable in many applications. But not always!*
        
       ___________________________________________________________________
       (page generated 2024-08-08 23:00 UTC)