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istatrol [2016/03/25 15:55] – Add These ISTA Devices Traumflug | istatrol [2018/05/27 16:10] (current) – external edit (unknown user) | ||
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on the command line. It should connect to the ISTAtrol and give a temperature readout every minute. That's how one makes visible how the ISTAtrol works. | on the command line. It should connect to the ISTAtrol and give a temperature readout every minute. That's how one makes visible how the ISTAtrol works. | ||
+ | **Note**: if the ISTAtrol was just started, it'll take some time until temperature readouts pick up, so be a bit patient. | ||
===== Valve Actuator ===== | ===== Valve Actuator ===== | ||
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{{ : | {{ : | ||
- | For the technical: ATtinys feature no Analog Digital Converter (ADC). But there is [[https:// | + | For the technical: ATtinys feature no Analog Digital Converter (ADC). But there is [[https:// |
As one can see by the coarse measurements done, this is linear enough for our purposes. The recorded pretty hefty hysteresis isn't a property of the thermistor or the ISTAtrol, it's an artefact of the measurement procedure. | As one can see by the coarse measurements done, this is linear enough for our purposes. The recorded pretty hefty hysteresis isn't a property of the thermistor or the ISTAtrol, it's an artefact of the measurement procedure. | ||
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This is a bit a tricker one. Moving the radiator valve usually doesn' | This is a bit a tricker one. Moving the radiator valve usually doesn' | ||
- | To get an idea about this dead time, connect ISTAtrol, run [[# | + | To get an idea about this dead time, connect ISTAtrol, run [[# |
==== PREDICTION_STEEPNESS ==== | ==== PREDICTION_STEEPNESS ==== | ||
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Such erratic behavior was actually the reason why ISTAtrol was developed. Consumption grew by 50% from one year to another, without visible reason. After optimisation (e.g. removing the table), bills are now not 50% up, but 60% down. Yikes! | Such erratic behavior was actually the reason why ISTAtrol was developed. Consumption grew by 50% from one year to another, without visible reason. After optimisation (e.g. removing the table), bills are now not 50% up, but 60% down. Yikes! | ||
+ | |||
+ | ===== TODO ===== | ||
+ | |||
+ | Let's collect possible improvements here. | ||
+ | |||
+ | ==== Bugs ==== | ||
+ | |||
+ | * Replacing the ATtiny2313 with an ATtiny4313. Program memory is so constrained that this is considered to be a bug. | ||
+ | * C3, 1.0 uF, should have a 200\_mil wide footprint. Many suppliers don't have 100\_mil types at this capacity. | ||
+ | * Key //Menu// should go to INT1 to allow triggering an interrupt. Crucial for allowing the MCU to go to sleep. | ||
+ | * These three thermistor connectors actually don't work this way. Connecting to means that current flows partially not to the measuring capacitor, but to the other ATtiny pin. Can likely solved with diodes, but note that a capacitor fills reasonably linear in the lower 20%, only. | ||
+ | |||
+ | ==== Wishlist ==== | ||
+ | |||
+ | * There is an internal voltage reference, which can be connected to the Analog Comparator. Does this work? Does the Brown Out Detector still work then, too? This could save a pair of resistors. See page\_149, " | ||
+ | * Voltage dividers for the 5\_V programmer should go into a separate cable adapter. | ||
+ | * Maybe it's a good idea to lift this whole thing to 5\_volts. Zener-diodes needed for D+ and D- then. ATtiny can run at 20\_MHz with quartz or 16.5\_MHz without quartz, then, both featuring considerably [[Notes on V-USB|smaller V-USB code]]. Voltage regulator can be dropped, but then the valve actuator motor needs some sort of voltage reduction. | ||
+ | * A display for allowing USB-less operations, of course. Could be done with SPI via the ISP connector. | ||
+ |
istatrol.1458917737.txt.gz · Last modified: 2018/05/27 16:10 (external edit)