Wednesday, April 01, 2009

Established standards Apple play fast 'n' loose with

  • RS422 - Of only minimal interest to the average user but RS422 is used extensively in television equipment. It is THE remote control protocol for driving VTRs/Telecines/effects machines etc. When Avid, Media 100 and IMmix VideoCube started delivering offline editing machines based on Macs in the early nineties they use the onboard RS422 serial ports to control the VTR and it works (just!). RS422 is a balanced serial standard where the Tx and Rx lines of an RS232 ports are balanced (either in a rep-coil or op-amp driving the line). Merely by providing a Tx pair and strapping one side of the pair to GND isn't good enough!
  • USB - I know the iMac was the first machine to popularise this now-ubiquitous interface but why do Apple provide USB cables with that little lump on the inner edge of the socket? I have to reach for a set of pliers every time I use an Apple USB extension!
  • SCSI - Apple have NEVER used the approved connector - from the very first Mac they used a 25-pin D type and when SCSI reached the v.3 spec (40MBytes per sec) with 50 or 68 pins for balanced working Apple pulled the same stunt as RS422 - balanced with one side of each pair tied to GND!
  • PCI - it's why you have to buy an Apple-specific version of any card more complicated than a USB card!
  • DVI - What was all that stuff with the Apple Cinema Display connector? It was just DVI in a different (more expensive) form.
  • EIDE CD/DVD drives - I lost count of the number of times I had to buy an Apple replacement optical drive that was a standard Sony/LG part but with APPLE FIRMWARE! A £50 drive that costs £250!

1 comment:

tim.burton said...

Mini Display Port - Why when display port isnt exactly bulky! Another £20 adaptor then!

Ditto applies for Mini DVI etc, at least Apple Cinema Display carried power to reduce cable clutter. The smaller connectors just served to make people carry around expensive woggles.