uint8t

Int variable input error for static uint8_t array

我是研究僧i 提交于 2019-12-11 15:49:11
问题 This is an extension from Input process and type for static uint8_t array regarding issues experienced from the suggested solution. Currently, I am trying to create both a int variable and a string variable with is inputted into a static uint8_t array and then is printed using Serial.println . I am using: #include <U8x8lib.h> Int Variable Code (Has Error): int world = 1; static uint8_t hello[sizeof(world)]; memcpy(hello, &world, sizeof(hello)); If I copy this directly and paste it into the

Why does bitwise left shift promotes an uint8_t to a wider type [duplicate]

为君一笑 提交于 2019-12-11 12:13:35
问题 This question already has answers here : What is going on with bitwise operators and integer promotion? (4 answers) C++ Unexpected Integer Promotion (2 answers) Closed 4 months ago . I was a bit messing around with uint8_t and was curious what happens when I outflow bits to the left and found that uint8_t i = 234; uint8_t j = (i << 1); auto k = (i << 1); std::cout << (int)j << std::endl; std::cout << k << std::endl; prints out 212 468 and not the expected 212 212 It seems like << does promote

How to add 5 seconds to a timer

旧街凉风 提交于 2019-12-11 03:57:01
问题 I'm trying to make a timer showing the following - hours : minutes : seconds : milliseconds. Here is my code: var timer = NSTimer() var startTime = NSTimeInterval() func updateTime() { var currentTime = NSDate.timeIntervalSinceReferenceDate() var elapsedTime : NSTimeInterval = currentTime - startTime let hours = UInt8(elapsedTime / 3600.0) elapsedTime -= (NSTimeInterval(hours) * 3600) let minutes = UInt8(elapsedTime / 60.0) elapsedTime -= (NSTimeInterval(minutes) * 60) let seconds = UInt8

Conversion between uint8 and char in C

人走茶凉 提交于 2019-12-11 01:45:40
问题 I have an API that implements a writing operation to EEPROM. Here is its declaration: CYBLE_API_RESULT_T CyBle_StoreAppData (uint8 * srcBuff, const uint8 destAddr[], uint32 buffLen, uint8 isForceWrite); It is working well when I call this function and send an array parameter to srcBuff which has been declared as uint8 type. The problem is, I need to send char array pointer to it. I was thinking that char is already a uint8 , but I get a compiler warning if I send a char array pointer to that

How to convert HEX string to UInt16?

徘徊边缘 提交于 2019-12-08 02:03:52
问题 I have a HEX string d285 and I want to convert it UInt16, please guide me how I can convert it. I tried this let buffer = UInt16("\(UInt8(text, radix: 16)!)") return Data(bytes: (buffer?.bigEndian.toBytes)!) but it's not working 回答1: UInt16 has an initializer that takes a string and radix value. This can be used to create UInt16 from string. let hexString = "d285" let hexToInt = UInt16(hexString, radix: 16) // prints 53893 回答2: let hexStr = "d285" var byteArr = [UInt8]() byteArr += hexStr

conversion of uint8_t to a string [C]

▼魔方 西西 提交于 2019-12-07 16:59:15
问题 I'm trying to "translate" an array of uint8_t [uint8_t lets_try[16]] to a string of 16*8+1[null character] elements. For example: lets_try[0] = 10101010 lets_try[1] = 01010101 ... and I would like to have a string like: 1010101001010101...[\0] Here the questions: 1) is there a quick way to perform this operation? I was trying to do it on my own; my idea was starting from translating a single uint8_t variable into a string and obtaining the full array with a loop [I haven't done this last part

conversion of uint8_t to a string [C]

给你一囗甜甜゛ 提交于 2019-12-05 20:19:39
I'm trying to "translate" an array of uint8_t [uint8_t lets_try[16]] to a string of 16*8+1[null character] elements. For example: lets_try[0] = 10101010 lets_try[1] = 01010101 ... and I would like to have a string like: 1010101001010101...[\0] Here the questions: 1) is there a quick way to perform this operation? I was trying to do it on my own; my idea was starting from translating a single uint8_t variable into a string and obtaining the full array with a loop [I haven't done this last part yet]. At the end I wrote this code: int main() { uint8_t example = 0x14; uint8_t *pointer; char *final

1 byte integer data type

浪子不回头ぞ 提交于 2019-12-04 07:50:49
I wrote the following code: #include <iostream> #include <iomanip> #include <stdint.h> using namespace std; int main() { uint8_t c; cin >> hex >> c; cout << dec << c; return 0; } But when I input c —hex for 12—the output is also c . I was expecting 12. Later I learned that: uint8_t is usually a typedef for unsigned char . So it's actually reading c as ASCII 0x63. Is there a 1 byte integer which behaves as an integer while doing I/O and not as char? Not that I know of. You could do the I/O using a wider integer type, and use range checking and casting as appropriate. I'm afraid I don't know of

How to read specific bits of an unsigned int

ε祈祈猫儿з 提交于 2019-12-02 05:57:03
问题 I have an uint8_t and I need to read/write to specific bits. How would I go about doing this. Specifically what I mean is that I need to write and then later read the first 7 bits for one value and the last bit for another value. edit: forgot to specify, I will be setting these as big endian 回答1: You're looking for bitmasking . Learning how to use C's bitwise operators: ~ , | , & , ^ and so on will be of huge help, and I recommend you look them up. Otherwise -- want to read off the least

How to read specific bits of an unsigned int

ε祈祈猫儿з 提交于 2019-12-02 03:18:50
I have an uint8_t and I need to read/write to specific bits. How would I go about doing this. Specifically what I mean is that I need to write and then later read the first 7 bits for one value and the last bit for another value. edit: forgot to specify, I will be setting these as big endian You're looking for bitmasking . Learning how to use C's bitwise operators: ~ , | , & , ^ and so on will be of huge help, and I recommend you look them up. Otherwise -- want to read off the least significant bit? uint8_t i = 0x03; uint8_t j = i & 1; // j is now 1, since i is odd (LSB set) and set it? uint8