uint8_t (C language - Type). uint8_t stores an 8-bit unsigned number, from 0 to 255. It is equal to unsigned char.
Questions tagged [uint8t]
272 questions
2
votes
2 answers
Casting int16_t to uint_8t*
I have a library driven result stored as an int16_t value (and it is a negative, which I can use the absolute value of) and another library function that requires this value a few steps later in the form uin8_t*. How can this be done without using…
Orbiting Eden
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2
votes
1 answer
uint8_t to String, leads to no output C++ (Beginner programer)
I'm a beginner at programming and I'm trying to build a program for raspberry pi in C++, I started with a program that ouput the UID on the console which was this
for(byte i = 0; i < mfrc.uid.size; ++i)
{
if(mfrc.uid.uidByte[i] < 0x10)
{
…
2
votes
2 answers
C++ How to convert a vector of size 4 into a 32 bit float
What is the fastest way to convert a vector of size 4 into a 32 bit float?
My failed attempt:
static bool vec2float32(std::vector bytes, float &result)
{
if(bytes.size() != 4) return false;
uint8_t sign = (bytes.at(0) &…
Blue7
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2
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1 answer
What is the fastest way to combine 8 uint8_t into a single uintmax_t?
I am looking to optimize a piece of code that uses popcnt to compute differences between uint8_ts. I figure it'd be faster to combine 8 uint8_ts into a single uintmax_t and use popcnt64 instead so that the popcnt operation doesn't have to be called…
Terry Martin
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2
votes
2 answers
Javascript reading local file to UInt8Array fast
How to read local binary file to UInt8Array fast. in below code
function readAllBytesAsUInt8Array(path) {
var req = new XMLHttpRequest();
req.open("GET", path, false);
req.overrideMimeType("text/plain; charset=binary-data");
…
user818117
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votes
1 answer
Why the size of uint8_t is 8 Byte after convert from 20Byte NSData in Objective-C?
I am developing in ios objective-c BLE , I receive the BLE data and print by NSLog like the following:
NSData *initialData = [characteristic value];
NSData *startOfFrameData = [initialData subdataWithRange:NSMakeRange(0,…
Wun
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2
votes
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Will a uint8_t array be terminated by null similar to a char array?
I am working on a project where the function will receive a pointer to a uint8_t array. I am to compare the contents of this with that of a pointer to unsigned char data buffer whose size is not known. I was hoping to use string based functions for…
Febin Sunny
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2
votes
1 answer
Sending string as Uint8 buffer
I'm developing a mobile app to communicate with Bluetooth Module. I'm sending data through android app & receiving it on BLE module.
I'm using cordova & BLE central plugin for cordova to communicate with the device from android.
App seems to work…
MANnDAaR
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2
votes
4 answers
C overflows inside an equation?
a + b overflows 255 back to 4 as I would expect, then c / 2 gives 2 as I expect. But then why does the last example not overflow when evaluating the same two steps?
I'm guessing the internal calculation values are stored with more bits, then only…
trapper
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3 answers
What happens to a value assigned to take up more than a types available space?
e.g.
uint8_t value = 256;
debug output:
0
I've read that it does some sort of truncating? I'm not seeing exactly how, any links are appreciated.
Womble
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2
votes
2 answers
split uint32 value to uint8 values in swift
in C I have
uint32 value = 39434;
uint8 firstByte = (unsigned char)value;
uint8 secondByte = (unsigned char)(value >> 8);
Is there any possibility to achieve the same in Swift?
Dimitrio
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2
votes
4 answers
Conversion between uint8 and char in C
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…
abdullah cinar
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converting char* to array of uint8_t (c)
I can make function calls and receive an array of strings that represents ipv6 adress. it looks something like this
char* buffer=resolver_getstring(config, INI_BOOT_MESHINTFIPADDRESS);
if i printed buffer i will gate the ipv6 adress in string…
lferasu
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2
votes
1 answer
Conversion of uchar array to uint8 type pointer
I want to convert a array of uchar to uint8 pointer. As both are of 8 bits and value ranges from 0 to 255 so I do not think it should cause and issue.
uchar list[100];
I have to pass above list to a function which accepts pointer to uint8t.
Can i…
Prannoy Mittal
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votes
3 answers
how to extract byte data from bluetooth heart rate monitor in objective c
Im having trouble understanding bytes and uint8_t values.
I am using the sample project created by apple that reads data from a Bluetooth 4.0 heart rate monitor via the heart rate service protocol. THe sample project gives out heart rate data as…
skeg0
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