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ANALOG DIGITIZER |
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UART CHIP 14469P
All models of digitizers, that I produced, had 32 channels of analog input. All models were channel agile, and would skip around under certain site operations. Otherwise, on a routine basis, each
digitizer would monitor each channel in numerical order. The digitizer scans from channel one to channel 32, skipping over any unused inputs.
Modern MCU chips have eliminated the need for big site digitizers. On the other hand, my independent MCU modules do not have the unboard hardware displays such as this. When you actually see the
display and witness the digitizing "in person" is gratifing. Or perhaps, I just like lights.
Main board
32 Chanel digitizer is being phased out. It still serves well.
16 inputs on the left, and 16 inputs on the right. Single ended: input and sig common on male header.
Under the old UART system, you cannot afford to loose a digitizer: the digitizer measures 32 parameters. The loss
would be catastrophic. But with the new system each MCU does its own digitizing. And a loss of one unit would only mean a few less eyes and controls. The system would still be viable.
This digitizer requires a dual power supply: a +12v and also a -12v. This is not a desirable situation. The object was to measure negative parameters. I wrestled with this problem for about a year,
and finally decided the solution was in the sensors. With negative sources, the sensor had the responsibility of polarity transformation. There was an additional problem of also logical inversion
of the parameter, but it was handled by the computer just fine. This solution also established a standardization of input signals. That standard, for me, became 0volts to 5volts. For example, if a
signal at the source swing from 0.5volts to .95volts, then the sensor had the responsibility of converting to 0volts to 5volts (also in the desired direction). The sensor then would deliver the
standardized parameter to the digitizer or MCU.
On a computer menu, you select what channel you want to calibrate. You then turn the pot to change the display.
Personally, I like the "hardware adjustment", rather than an adjustment on a computer screen. This method gives emediate gratification, and is so intuitive, clear and direct. However, there is one
digitizer that everone complains about: I wired every pot in backwards. This makes clockwise down, and couterclockwise up. My mistake totally nullified the advantages, and took away my
friends.
CognizantWire Systems