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Topic: not understanding 7 segment multiplexing (Read 5831 times) previous topic - next topic

magnethead794


Are you putting down discrete pads vs chip symbols? Makes it hard to follow what you are doing.

Pic's are coming thru nice.


not sure exactly what you mean?

and I'm printing to A0 paper PDF as ~4x scale or so then converting to jpg.
KF5RVR

CrossRoads

Here's what I mean.
I layed out 10 LEDs, 2 resistors, a connector.
The board layout looks like it.
Yours just looks like a bunch of holes that are connected, can't tell what it is.
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

magnethead794

#47
Jan 11, 2012, 07:36 am Last Edit: Jan 11, 2012, 07:57 am by magnethead794 Reason: 1

Here's what I mean.
I layed out 10 LEDs, 2 resistors, a connector.
The board layout looks like it.
Yours just looks like a bunch of holes that are connected, can't tell what it is.



I'm a beginner so you have to bear with me learning my way through eagle.

so if I go per http://arduino.cc/en/Tutorial/ArduinoToBreadboard minimalist approach and don't use a resonator/crystal, it will function at 1 MHz, right?

so 9600bps serial in code will actually be 9600/16 = 600bps?

If board space gets tight, I may need that extra little bit of space in leu of resonator. Didn't realize how hard it was going to be to fit all this stuff on a 2" square board. I'm gonna see how far I can get.
KF5RVR

CrossRoads

I am not sure, I have not operated at other than 16 MHz in my designs.
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

magnethead794

I tallied it up. I can buy SF's small indicator cheaper than I can build it, when you calculate time. Maybe they'll have a new revision with mounting holes, if not, I came up with a mounting method. I thought about it, and having a 10K resistor on the VCC line shold somewhat make up for not having on on each digit supply.
KF5RVR

magnethead794

Here's where KirAsh and I landed. Only have to make 2 boards. Use the sparkfun board for indication, and use the selector board to run the Tx to the indicator and SPI to the shift registers. On the shift boards, the first one gets +12/+5/gnd through a 3 position terminal block, SPI over the Cat5, then it all gets passed on from pin headers.

http://i1105.photobucket.com/albums/h355/magnethead494/shift_board_brd.jpg

http://i1105.photobucket.com/albums/h355/magnethead494/shift_board_sch.jpg

http://i1105.photobucket.com/albums/h355/magnethead494/dial_board_selector_brd.jpg

http://i1105.photobucket.com/albums/h355/magnethead494/dial_board_selector_sch.jpg
KF5RVR

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