bionlottery.blogg.se - Windows 10 rpn scientific calculator english

#WINDOWS 10 RPN SCIENTIFIC CALCULATOR ENGLISH UPDATE#
#WINDOWS 10 RPN SCIENTIFIC CALCULATOR ENGLISH SOFTWARE#

I discovered that in fact the STM32 was put into STOP1 mode, while there is a more economic one, STOP2, which, however, takes longer startup time (does not matter in my case). Previously the calculator consumed 40-55 uA of current from the 3V battery, which was to my knowledge a bit on a higher side of what one should expect from STM32L476 in STOP mode. I think I've solved all my problems with power consumption being somewhat higher than I hoped.

Power consumption: solved Anton Poluektov.

More compact PCB (126圆4 mm) with screw holes and cutout for LCD flat cable.

Improved PCB layout for TPS61222 voltage booster (following datasheet).

New battery holder (Keystone 1057) which sits in the cutout of the PCB to reduce thickness of the enclosure.

Two Schottky diodes as a protection when both ST-Link and battery power is on, and to protect from reverse battery polarity.

Power pin on ST-Link header to power the calculator while flashing or to measure current consumption.

Tantalum capacitor (220 uF) in parallel to the battery to avoid voltage drops during heavy processor activity when the battery is weak.

Additional filtering capacitors for STM (one per each pair of VSS/VDD(A) inputs as per datasheet) and for the LCD (according to LS027B7DH01 datasheet).

#WINDOWS 10 RPN SCIENTIFIC CALCULATOR ENGLISH UPDATE#

Low power consumption (~10 uA in standby mode with LCD display on, 2-3 uA with LCD off).īased on my experience with the first version, I've made an update of the schematics and the v2 of the PCB is now ordered.

#WINDOWS 10 RPN SCIENTIFIC CALCULATOR ENGLISH SOFTWARE#

Something that I've never seen in any of the hardware calculators, and very rarely is present in the software ones. Calculations with uncertainties using error-propagation formulas (UNCERT mode).Fixed, scientific (SCI) and engineering (ENG) display modes (including SI prefixes in ENG mode), variable 3-10 digits precision.Error function (erf) and its inverse (erfinv)."Standard" scientific calculator functions (trigonometric, logarithms, exponentiation, square root and power).Reverse Polish notation with 4-element stack.For the moment, while the software is under development, the buttons are labeled with a simple laserjet-printable sticker paper. The two parts of the case are held together by simple snap fit joints, no screws are needed. The case and keyboard is made of four 3D printed parts (top and bottom parts of the case, keypad and switch spacer). All electronics runs off the 3V lithium battery (CR2032) that should be sufficient to provide power for several years of operation.

Keyboard uses light-touch tactile switches Panasonic EVQQ2B01W (50g actuation force). The display is the famous Sharp memory LCD module LS027B7DH01 (400x240 pixel monochrome). The calculator is based on low-power 32-bit ARM microcontroller STM32L476 running at 8 MHz, which is more than sufficient for the purpose.