Hi Bill,I'm using a Mega 2560 board. I'm still in early development but am looking at all power considerations. Once the firmware is ready I'll be able to more accurately measure power draw. Thanks for the 9v / AA battery tip, can I simply connect a battery powered USB 'dongle' (Energizer for example) to the board for power?When ground is removed from the lcd and is restored a minute or so later, all the pixels return as previously initialized. It seems perfect, so far.I'll pm you those fonts.Regards,J
Have you actually measured the current draw for the logic itself? It's supposed to be incredibly low i.e. may not be worth worrying about.
Quote from: Telek on Oct 31, 2011, 10:48 pmHave you actually measured the current draw for the logic itself? It's supposed to be incredibly low i.e. may not be worth worrying about.No I haven't done any measuring yet but surely the lcd being on shortens run time on a battery. Today a dual relay was implemented to turn off the lcd 5v & ground after a pre-set amount of time and it works nicely. The lcd is also re-initialized when it powers back up.I'm wondering though, can this be done without relays?J
I'm not as familiar with your controller, but in standby my measurements on my KS0713 LCD controller were in the range of 50uA - basically not enough to worry about as the leakage current of any switching device while in the ON state overshadowed the savings in power OFF state.
You certainly should be able to use a simple NPN transistor (2N2222 or 2N3904) on the ground line in place of the relay. But keep in mind that any device is going to require power to operate which may negate any savings over just leaving the device in standby mode. Also the increased cost may not be worth it if it's a production unit. Adding a larger battery pack is also a valid option, or a small solar panel.
#define lcdDelayNanoseconds(__ns) asm("nop") // not sure but it works
/* For PIC32 */#define __PIC32MX__ 1 /* For Uno32 */#define __32MX320F128H__ 1 /* For Max32 */#define __32MX795F512L__ 1
I have looked at using serial mode in the past. It would be great to reduce the number of pins,but as I recall, many of the displays, (and I believe this one as well), lose the abilityto read from the display when using their built in serial mode.Currently the library code goes through many painful gyrations to avoid the use of a frame buffer.It was a conscious decision to eat up additional flash space to avoid using much RAMso that the library could function on all arduino boards including those like the m168 thatonly have 1k of ram, which would never be able to support a frame buffer for a 128x64 display.The current code can support any sized display up to 256x256 without using up any additionalRAM.