Re: 8 Battery Lead Acid Slave Board
Posted: Wed Feb 23, 2011 8:28 pm
RESULT
Using just the LM393 comparator, I can get 300 baud serial.
Using an op-amp first I can get 1200 baud serial
The phototransistor can't drive a 10K pulldown so I am using 39K. I wonder if I could omit the comparator now or use the other op-amp on the LM393 with positive feedback as a comparator and that would reduce the package count. I'm not finished tinkering yet! I have been using the dual trace feature on my oscilloscope tonight, I feel so like a scientist
I like the sound of using pulsin for the slavebus and using serial on the masterbus to talk back to the master. I've been fleshing out my ideas for the software and will hack it together pretty soon I think.
Tomorrow, I'll play with the hall sensor and LM393 to see if I can make a propshaft speed sensor to ping the opto input on the master board.
Having fun with this now
Derek
EDIT: The picaxe connects to pin 1 on the LM393, missed it on the schematic
It still works with just the op-amp but it looks better on the scope with the comparator and the ability to adjust the threshold makes it easier to dial in the proper logic levels.
Using just the LM393 comparator, I can get 300 baud serial.
Using an op-amp first I can get 1200 baud serial
The phototransistor can't drive a 10K pulldown so I am using 39K. I wonder if I could omit the comparator now or use the other op-amp on the LM393 with positive feedback as a comparator and that would reduce the package count. I'm not finished tinkering yet! I have been using the dual trace feature on my oscilloscope tonight, I feel so like a scientist
I like the sound of using pulsin for the slavebus and using serial on the masterbus to talk back to the master. I've been fleshing out my ideas for the software and will hack it together pretty soon I think.
Tomorrow, I'll play with the hall sensor and LM393 to see if I can make a propshaft speed sensor to ping the opto input on the master board.
Having fun with this now
Derek
EDIT: The picaxe connects to pin 1 on the LM393, missed it on the schematic
It still works with just the op-amp but it looks better on the scope with the comparator and the ability to adjust the threshold makes it easier to dial in the proper logic levels.