transistor | https : //crates.io/crates/transistor

I'm trying to build a small hygrometer based on the DHT11 and I'm having a bit of an "issue" with the code size. I want to run it on an Attiny45 and it's a wee bit too big (352 bytes too big to be exact). I am aware that I could just use an Attiny85 and have space to spare or don't use a bootloader and barely fit it in (94%) but I kind of want to make my life harder than it needs to be and figure out how to reduce size since it'll probably come in handy in the future. Treat it as a learning experience if you will.

What it's supposed to do:

• Read DHT11 input
• Display results on 2 two-digit 7-segment displays (so I guess 4 7-segments in total)
• Go to sleep most of the time to preserve battery
• Wake up every 8 seconds to update sensor values (without turning on the display)
• Wake up on a button press to display the values for humidity and temperature

Side note: 7-segments are adressed via two 74HC595s of which I am using 7 outputs each for the displays and 1 each for a transistor that connects the display in question to GND. There's a schematic at the bottom if you're interested.

As pointed out, my main issue is code size so if anyone has any tips on how to reduce that (or any other tips how to improve the code) please let me know.

I hope I'm asking the question properly, if not please let me know.

Compiler output:

I want to read the below CSV file into read_csv, due to the special characters in the CSV file , cant read the file properly, missing special characters in the column names in the data frame , and data is going here and there, but excel data is showing properly. can you help to fix this issue, want to skip 5 rows and read the remaining data as it is and rename the column name

CSV file:- $$PROGRAM$$ transistor.csv
$$DEVICE$$ 1
$$LOT$$ lot
$$DATE$$ 7/28/2021

$$FORMAT$$ ,SERIAL,COND=Temp,COND=vdd
1,BA1,25,1.2,7/12/201
1,BA2,25,1.2
1,BA2,25,1.2
1,BA3,25,1.2

I'm writing some code to simulate a computer at the transistor level. The emulator boils down to a graph where each node is a transistor, and each edge is a wire connecting any two transistor nodes on the graph. This graph is cyclic, and transistor nodes may be connected to themselves.

To run a single "step" of the emulator, two separate functions are run:

1. Each wire edge is processed, setting the input of its target node from the output of its source node. Each wire is visited exactly once each step, but a transitor may be visited multiple times.
2. Each transistor node output state is updated from its input's states (how is outside the scope of this question, I'm pretty sure I'm doing it efficiently).

I believe I have the second step optimised, but I need help making the first step more efficient.

The code looks roughly like this:

I have a rich text document (.rtf) that has notes separated by dates. It follows the format below:

2021-4-6

Some notes

Hyperlink

More text

2021-4-5

Notes notes notes

I'd like to split the document so that there is a different file for each date with the corresponding notes saved and the date as the file name. The split command seemed close to what i wanted but it doesn't seem to be able to account for the variable amount of text and lines for each day. Would a bash script work for this? I'm new to this so forgive me if the answer is obvious. Edit: the document contains some leading spaces and blank lines.

An example input file:

2020-11-15

How to properly use a NanoVNA V2 Vector Network Analyzer (Tutorial) - YouTube - VNA NanoVNA

Impedence matching an antenna Reflection VNA vs Spectrum Analyzer? Usually impedence of 50 ohms VSWR Meter SWR - Standing Wave Ratio SWR = 1 means there is no reflected power

2020-11-11

Superheterodyne receiver - Wikipedia - A superheterodyne receiver, often shortened to superhet, is a type of radio receiver that uses frequency mixing to convert a received signal to a fixed intermediate frequency (IF) which can be more conveniently processed than the original carrier frequency. Protected Cell Unprotected Cell Logic Gates from Transistors: Transistors and Boolean Logic - YouTube -

Would be split into two files:

2020-11-15.rtf

2020-11-15

How to properly use a NanoVNA V2 Vector Network Analyzer (Tutorial) - YouTube - VNA NanoVNA

Impedence matching an antenna Reflection VNA vs Spectrum Analyzer? Usually impedence of 50 ohms VSWR Meter SWR - Standing Wave Ratio SWR = 1 means there is no reflected power

2020-11-11.rtf

2020-11-11

Superheterodyne receiver - Wikipedia - A superheterodyne receiver, often shortened to superhet, is a type of radio receiver that uses frequency mixing to convert a received signal to a fixed intermediate frequency (IF) which can be more conveniently processed than the original carrier frequency. Protected Cell Unprotected Cell Logic Gates from Transistors: Transistors and Boolean Logic - YouTube -

The following data represent the lifetimes (in hours) of a sample of 40 transistors:

I am getting a little bit deeper in exploring the STM32's MCU and I went bare metal. I am using an STM32F103C8T6 BluePill.

Just to make sure I'm fully understanding what is going on, what is the nature of the addresses of the MCU? I mean, for my board, the RCC boundary address is 0x4002 1000 - 0x4002 13FF and by creating a custom named pointer to this address and type casing this "0x40021000" to be treated as an actual address by the compiler, is this an address of an actual register?

I mean what I understood is that the MCU has 32bit registers, those registers have addresses, those addresses are the addresses of the registers and each 32bit register in the MCU has a unique address, a physical one! And therefore to manipulate a specific register we create a pointer to the address of that register and then dereferencing the pointer and change the register it is pointing to.

For example, the RCC address starts at "0x40021000" and this address is of the register 0x0000XX83 (where X is undefined as per the reference manual), Am I right? Do those registers actually have addresses in the MCU so they can be accessed and manipulated? If so, are those registers bits are just transistors where when setting a bit in that register to 1 the transistor turns on?

Also if what I understood was correct, does that mean that the Reset Values are the actual register values which have addresses (as in registers are analogous to variables e.g x,y, etc.. and there addresses are those in the reference manual as in RCC address = 0x40021000 and dereferencing this address gives us 0x0000XX83 ??

I know I might have confused you but this is the best I can explain! Thank you in advance.

Recently I've been trying to use a wired Xbox 360 controller to interface with my Arduino Uno (via Processing) that I'm using in a test circuit to control two brushed motors. I came across this video that uses the library to control a single servo motor along with videos made by the library's author. I made a few modifications to the code (from the first link) just to support the two motors, and it works (sort of). The only problem is that it accepts input from my Bluetooth mouse instead of the Xbox controller which are both connected to my laptop's USB ports. I set the text configuration file so that "Button 0" and "Button 2" -which correspond to the A and X buttons respectively- make two pins on the Arduino go high which feed into the bases of two transistors that control the motors. Instead, the left mouse button and scroll wheel button on my Bluetooth mouse controls these outputs.

I'm a bit confused about why this is happening and I've tried a few different things to resolve the issue. I thought that when creating the configuration file (with a program that comes with the library) I accidentally choose my mouse as the input device, so I made another configuration file just to make sure that this wasn't the case, though I'm not exactly sure what in the configuration file indicates the correct device to use. Maybe I'm missing something extremely obvious, I just know that I need a second set of eyes to look things over for me. If you have experience with this library your help would be much appreciated, thank you.

/////////////////////////////////////////////////////////////////////////////////////////////////////////

Configuration File:

Is there some simple way to avoid shorting the pins of a FET?

Preamble: after working a couple of years as application developer, the world of the software engineering became more obscure than it was before. The reason is that the real stuff is hidden under zillions layers of abstractions: OS, frameworks, etc. The young generation is deprived of the pleasure of working with PDP-like machines where all programming was done via electrical switch toggling. Another problem is the ephemeral nature of modern programming languages. Once there was Python 2.x, now it is deprecated and there is Python 3.x which in its turn will be deprecated in a couple of months. Idem for other languages. ANSI C looks like the Pyramid of Cheops: it was there in 70's and I don't doubt it will be there after the Sun will become a red dwarf.

It seems that now the only way to understand the interaction between the hardware and the software is to play with embedded development. From the pedagogical point of view physical chips are very handy because they allow to tackle the most difficult part of C language, namely pointers. When coding in OS environment, */& notation is still very confusing because it refers to some location somewhere inside of the virtual memory. And before you will got the understanding of what is the virtual memory, you have to read a couple of monographs about OS development, etc. You may find it stupid but I do really want to know which transistor is holding my bit right now. At least, I can wire physical pin voltage to programming abstractions.

Currently I am working with Atmel chips and WinAVR package because of numerous textbooks and accessible hardware. Though all books promise to teach AVR coding using plain C, the reality is that all pointers are hidden behind macros like PORTA, DDRB, etc. All code examples include header file 'io.h' which in its turn refers to other header files specific for a given chip like 'iomx8.h'. So far, I cannot find any macros definition in these headers. The code to increase the voltage on the physical pin 14 on Atmega168 looks like