Archived posting to the Leica Users Group, 2003/02/23
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Frank, > For all you expecting to use FPGA in a future incarnation of a M7 control > circuit, I recommend you think through the problem of converting > the analog > voltage picked up by the light sensor and converting it to digital so the > digital control parts can do their job.....There is not to my knowledge an > FPGA that has an A/D converter block. Sure, it is possible to use an FPGA > plus an external A/D, but now the size is bigger and the power greater. The point of the FPGA is that it can emulate any digital circuitry, it was merely an example posed because Jerry said that it would require custom chips to do this. Also, FPGAs can in fact do very decent A/D converters with little external circuitry. Also, A/Ds are very cheap and small, and don't consume much power. > OTOH, for about $1 you can buy a low end uP ( uController) that > has a built > in A/D, lots of registers for counting time, digital outputs for running > LED's and motor/solenoid control circuits, and is programmable. > It runs on > low voltages and low current. Agreed, but whether that is or is not capable of doing the job, depends on exactly what the job is. It may not have enough I/O for driving the display and taking in all the inputs. > If Austin can find out the answer on the electronic contents of the M6 and > M7 shutter control circuitry, we will have a definitive answer ( from the > horses' mouth).... I am not questioning the M6, only the M7. I believe the M6 should be all analog. Austin - -- To unsubscribe, see http://mejac.palo-alto.ca.us/leica-users/unsub.html