I'm currently trying to set up a fermentation specific gravity monitor, using a tilt sensor. The process can take several weeks, and must be contained in a sterile container, so must be battery powerered. I'm using a slightly modified ESP8266-01, which enters sleep mode then wakes once an hour to take a measurement, transmit the data, and return to sleep mode. I'm using an MPU6050 for the tilt sensor. Firstly, I can't seem to put the mpu into sleep mode when the esp is off, it always seems to take around 4mA, and secondly, I only need one axis, is it possible to disable everything else to limit power consumption further? I can't seem to find anything in the manual to disable axis, only to calibrate them. my code is below
experimenting with the registers below seem to make no difference, adding them, taking them out altogether, still takes around 4mA. Tried setting to 1 to put the mpu to sleep at the end of the cycle but makes no difference.
Wire.write(0x6B);
Wire.write(0);
I'm very new to this and im struggling to interpret the manual when it refers to bit6 in addr 6b, how do i set bit 6?
If i could restict the mpu to only 1 axis, no acceleration, and to deep sleep inbetween measurements I should be able to get the power consumption around 0.5mA which gives me agood battery life using a single 18650. Any advice would be greatly appreciated!
#include <ESP8266WiFi.h>
#include <PubSubClient.h>
#include <OneWire.h>
#include <DallasTemperature.h>
#include "MPU6050.h"
#include "I2Cdev.h"
#include "Wire.h"
// Update these with values suitable for your network.
const char* ssid = "****";
const char* password = "******";
IPAddress server(192, 168, 1, 90);
WiFiClient espClient5;
PubSubClient client(espClient5);
long lastMsg = 0;
char msg[50];
const uint8_t scl = 5; //D1
const uint8_t sda = 4; //D2
int val;
int prevVal = 0;
String pubString;
char gravity[50];
MPU6050 mpu;
const int sleepTimeS = 10; //only 10 seconds for testing purposes, set to
1hr when operational
int counter=0;
int16_t ax, ay, az;
int16_t gx, gy, gz;
void setup_wifi() {
delay(10);
// We start by connecting to a WiFi network
Serial.println();
Serial.print("Connecting to ");
Serial.println(ssid);
WiFi.begin(ssid, password);
while (WiFi.status() != WL_CONNECTED) {
delay(500);
Serial.print(".");
}
randomSeed(micros());
Serial.println("");
Serial.println("WiFi connected");
Serial.println("IP address: ");
Serial.println(WiFi.localIP());
}
void callback(char* topic, byte* payload, unsigned int length) { //not
required in this application
}
void reconnect() {
// Loop until we're reconnected
while (!client.connected()) {
Serial.print("Attempting MQTT connection...");
// Create a random client ID
String clientId = "test";
clientId += String(random(0xffff), HEX);
// Attempt to connect
if (client.connect(clientId.c_str())) {
Serial.println("connected");
// Once connected, publish an announcement...
client.publish("AliveRegister", "FermentMon");
} else {
Serial.print("failed, rc=");
Serial.print(client.state());
Serial.println(" try again in 5 seconds");
// Wait 5 seconds before retrying
delay(5000);
}
}
}
#define ONE_WIRE_BUS 2 // D4 on physical board
OneWire oneWire(ONE_WIRE_BUS);
DallasTemperature DS18B20(&oneWire);
float prevTemp = 0;
void setup() {
counter = 0;
Serial.begin(9600);
Wire.begin(0,2);
Wire.write(0x6B); //PWR_MGMT_1 register
Wire.write(0); // set to zero wakes teh 6050
Wire.endTransmission(true);
delay(100);
setup_wifi();
client.setServer(server, 1883);
client.setCallback(callback);
if (!client.connected()) {
reconnect();
}
Serial.println("Initialize MPU");
mpu.initialize();
Serial.println(mpu.testConnection() ? "Connected" : "Connection failed");
float temp;
DS18B20.requestTemperatures();
temp = DS18B20.getTempCByIndex(0); // first temperature sensor
char buff[100];
dtostrf(temp, 0, 2, buff);
temp = temp + 0.5;
int tRound = int(temp);
client.publish("Fermenter/temperature", buff);
Serial.print("Fermenter Temperature: ");
Serial.println(temp);
prevTemp = tRound;
mpu.getMotion6(&ax, &ay, &az, &gx, &gy, &gz);
val = map(ax, -17000, 17000, 0, 180);
pubString = String(val);
pubString.toCharArray(gravity, pubString.length() + 1);
client.publish("Fermenter/angle", gravity);
Serial.print("Gravity angle: ");
Serial.println(val);
delay(500);
// counter = counter+1;
Serial.println("sleep mode");
Wire.write(0x6B); //PWR_MGMT_1 register
Wire.write(1); // set to zero wakes teh 6050
// sleep
ESP.deepSleep(sleepTimeS * 1000000);
delay(2000);
}
void loop() {
client.loop();
}
I'm very new to this and im struggling to interpret the manual when it refers to bit6 in addr 6b, how do i set bit 6?
Setting a bit is simple.
Use the follow functions to avoid any brain storming.
// Write register bit
void writeRegisterBit(uint8_t reg, uint8_t pos, bool state)
{
uint8_t value;
value = readRegister8(reg);
if (state)
{
value |= (1 << pos);
}
else
{
value &= ~(1 << pos);
}
writeRegister8(reg, value);
}
// Write 8-bit to register
void writeRegister8(uint8_t reg, uint8_t value)
{
Wire.beginTransmission(MPU_addr);
#if ARDUINO >= 100
Wire.write(reg);
Wire.write(value);
#else
Wire.send(reg);
Wire.send(value);
#endif
Wire.endTransmission();
}
Example Usage: writeRegisterBit(MPU6050_REG_INT_PIN_CFG, 5, 1); //Register 37;Interrupt Latch Enable
For your application:
void acclSetSleepEnabled(bool state)
{
writeRegisterBit(MPU6050_REG_PWR_MGMT_1, 6, state);
}
If i could restict the mpu to only 1 axis, no acceleration, and to deep sleep inbetween measurements I should be able to get the power consumption around 0.5mA which gives me agood battery life using a single 18650
To enter low power accelerometer mode use the following function:
void lowPowerAccel(uint8_t frequency) {
uint8_t value;
value = readRegister8(MPU6050_REG_PWR_MGMT_2);
value &= 0b00111000;
value |= (frequency << 6) | 0b111;
writeRegister8(MPU6050_REG_PWR_MGMT_2, value);
value = readRegister8(MPU6050_REG_PWR_MGMT_1);
value &= 0b10010111;
value |= 0b00111000;
writeRegister8(MPU6050_REG_PWR_MGMT_1, value);
}
This lowPowerAccel function also puts the gyro to standy mode. The function needs a wake up frequency parameter.
This is defined as follows:
/*
* LP_WAKE_CTRL | Wake-up Frequency
* -------------+------------------
* 0 | 1.25 Hz
* 1 | 2.5 Hz
* 2 | 5 Hz
* 3 | 10 H
*/
#define LP_WAKE_CTRL_1_25 0x00
#define LP_WAKE_CTRL_2_5 0x01
#define LP_WAKE_CTRL_5 0x02
#define LP_WAKE_CTRL_10 0x03
I hope, I could answer some of your questions.
Good luck! :)
Are you using a breakout board for the MPU6050? e.g. GY-521. Often they use linear regulators and leds which will consume additional power. It may be necessary to remove these and run the IMU from a direct power source.
Each register in the MPU6050 is 8 bits wide. When setting an individual bit to a desired value you can either use bitwise manipulation (not practical here as we aren't directly interacting with the registers) or directly set all of the bits in the register to the register's new state e.g. 0b00100000 ~ 0x20. Instead of writing a 1 to 0x6B when attempting to put the MPU6050 to sleep you should be writing 0x20.
https://www.invensense.com/wp-content/uploads/2015/02/MPU-6000-Register-Map1.pdf
Referencing page 40-42, if you want to take things a step further you can disable the temperature sensor, accelerometers, and redundant gyroscope axes to save power while the device is active.
What would be an efficient way to optimize the following code with sse ?
uint16_t change1= ... ;
uint8_t* pSrc = ... ;
uint8_t* pDest = ... ;
if(change1 & 0x0001) *pDest++ = pSrc[0];
if(change1 & 0x0002) *pDest++ = pSrc[1];
if(change1 & 0x0004) *pDest++ = pSrc[2];
if(change1 & 0x0008) *pDest++ = pSrc[3];
if(change1 & 0x0010) *pDest++ = pSrc[4];
if(change1 & 0x0020) *pDest++ = pSrc[5];
if(change1 & 0x0040) *pDest++ = pSrc[6];
if(change1 & 0x0080) *pDest++ = pSrc[7];
if(change1 & 0x0100) *pDest++ = pSrc[8];
if(change1 & 0x0200) *pDest++ = pSrc[9];
if(change1 & 0x0400) *pDest++ = pSrc[10];
if(change1 & 0x0800) *pDest++ = pSrc[11];
if(change1 & 0x1000) *pDest++ = pSrc[12];
if(change1 & 0x2000) *pDest++ = pSrc[13];
if(change1 & 0x4000) *pDest++ = pSrc[14];
if(change1 & 0x8000) *pDest++ = pSrc[15];
So far I am using a quite big lookup table for it, but I really want to get rid of it:
SSE3Shuffle::Entry& e0 = SSE3Shuffle::g_Shuffle.m_Entries[change1];
_mm_storeu_si128((__m128i*)pDest, _mm_shuffle_epi8(*(__m128i*)pSrc, e0.mask));
pDest += e0.offset;
Assuming:
change1 = _mm_movemask_epi8(bytemask);
offset = popcnt(change1);
On large buffers, using two shuffles and a 1 KiB table is only ~10% slower than using 1 shuffle and a 1MiB table. My attempts at generating the shuffle mask via prefix sums and bit twiddling are about about half the speed of the table based methods
(solutions using pext/pdep were not explored).
Reducing table size: Use two lookups into a 2 KiB table instead of 1 lookup into a 1 MiB table. Always keep the top-most byte - if that byte is to be discarded then it doesn't matter what byte is at that position (down to 7-bit indices, or 1 KiB table). Further reduce possible combinations by manually packing the two bytes in each 16-bit lane (down to a 216 byte table).
The following example strips whitespace from text using SSE4.1. If only SSSE3 is available then blendv can be emulated. The 64-bit halves are re-combined by overlapping writes to memory, but they could be re-combined in the xmm register (as seen in the AVX2 example).
#include <stdint.h>
#include <smmintrin.h> // SSE4.1
size_t despacer (void* dst_void, void* src_void, size_t length)
{
uint8_t* src = (uint8_t*)src_void;
uint8_t* dst = (uint8_t*)dst_void;
if (length >= 16) {
// table of control characters (space, tab, newline, carriage return)
const __m128i lut_cntrl = _mm_setr_epi8(' ', 0, 0, 0, 0, 0, 0, 0, 0, '\t', '\n', 0, 0, '\r', 0, 0);
// bits[4:0] = index -> ((trit_d * 0) + (trit_c * 9) + (trit_b * 3) + (trit_a * 1))
// bits[15:7] = popcnt
const __m128i sadmask = _mm_set1_epi64x(0x8080898983838181);
// adding 8 to each shuffle index is cheaper than extracting the high qword
const __m128i offset = _mm_cvtsi64_si128(0x0808080808080808);
// shuffle control indices
static const uint64_t table[27] = {
0x0000000000000706, 0x0000000000070600, 0x0000000007060100, 0x0000000000070602,
0x0000000007060200, 0x0000000706020100, 0x0000000007060302, 0x0000000706030200,
0x0000070603020100, 0x0000000000070604, 0x0000000007060400, 0x0000000706040100,
0x0000000007060402, 0x0000000706040200, 0x0000070604020100, 0x0000000706040302,
0x0000070604030200, 0x0007060403020100, 0x0000000007060504, 0x0000000706050400,
0x0000070605040100, 0x0000000706050402, 0x0000070605040200, 0x0007060504020100,
0x0000070605040302, 0x0007060504030200, 0x0706050403020100
};
const uint8_t* end = &src[length & ~15];
do {
__m128i v = _mm_loadu_si128((__m128i*)src);
src += 16;
// detect spaces
__m128i mask = _mm_cmpeq_epi8(_mm_shuffle_epi8(lut_cntrl, v), v);
// shift w/blend: each word now only has 3 states instead of 4
// which reduces the possiblities per qword from 128 to 27
v = _mm_blendv_epi8(v, _mm_srli_epi16(v, 8), mask);
// extract bitfields describing each qword: index, popcnt
__m128i desc = _mm_sad_epu8(_mm_and_si128(mask, sadmask), sadmask);
size_t lo_desc = (size_t)_mm_cvtsi128_si32(desc);
size_t hi_desc = (size_t)_mm_extract_epi16(desc, 4);
// load shuffle control indices from pre-computed table
__m128i lo_shuf = _mm_loadl_epi64((__m128i*)&table[lo_desc & 0x1F]);
__m128i hi_shuf = _mm_or_si128(_mm_loadl_epi64((__m128i*)&table[hi_desc & 0x1F]), offset);
// store an entire qword then advance the pointer by how ever
// many of those bytes are actually wanted. Any trailing
// garbage will be overwritten by the next store.
// note: little endian byte memory order
_mm_storel_epi64((__m128i*)dst, _mm_shuffle_epi8(v, lo_shuf));
dst += (lo_desc >> 7);
_mm_storel_epi64((__m128i*)dst, _mm_shuffle_epi8(v, hi_shuf));
dst += (hi_desc >> 7);
} while (src != end);
}
// tail loop
length &= 15;
if (length != 0) {
const uint64_t bitmap = 0xFFFFFFFEFFFFC1FF;
do {
uint64_t c = *src++;
*dst = (uint8_t)c;
dst += ((bitmap >> c) & 1) | ((c + 0xC0) >> 8);
} while (--length);
}
// return pointer to the location after the last element in dst
return (size_t)(dst - ((uint8_t*)dst_void));
}
Whether the tail loop should be vectorized or use cmov is left as an exercise for the reader. Writing each byte unconditionally/branchlessly is fast when the input is unpredictable.
Using AVX2 to generate the shuffle control mask using an in-register table is only slightly slower than using large precomputed tables.
#include <stdint.h>
#include <immintrin.h>
// probably needs improvment...
size_t despace_avx2_vpermd(const char* src_void, char* dst_void, size_t length)
{
uint8_t* src = (uint8_t*)src_void;
uint8_t* dst = (uint8_t*)dst_void;
const __m256i lut_cntrl2 = _mm256_broadcastsi128_si256(_mm_setr_epi8(' ', 0, 0, 0, 0, 0, 0, 0, 0, '\t', '\n', 0, 0, '\r', 0, 0));
const __m256i permutation_mask = _mm256_set1_epi64x( 0x0020100884828180 );
const __m256i invert_mask = _mm256_set1_epi64x( 0x0020100880808080 );
const __m256i zero = _mm256_setzero_si256();
const __m256i fixup = _mm256_set_epi32(
0x08080808, 0x0F0F0F0F, 0x00000000, 0x07070707,
0x08080808, 0x0F0F0F0F, 0x00000000, 0x07070707
);
const __m256i lut = _mm256_set_epi32(
0x04050607, // 0x03020100', 0x000000'07
0x04050704, // 0x030200'00, 0x0000'0704
0x04060705, // 0x030100'00, 0x0000'0705
0x04070504, // 0x0300'0000, 0x00'070504
0x05060706, // 0x020100'00, 0x0000'0706
0x05070604, // 0x0200'0000, 0x00'070604
0x06070605, // 0x0100'0000, 0x00'070605
0x07060504 // 0x00'000000, 0x'07060504
);
// hi bits are ignored by pshufb, used to reject movement of low qword bytes
const __m256i shuffle_a = _mm256_set_epi8(
0x7F, 0x7E, 0x7D, 0x7C, 0x7B, 0x7A, 0x79, 0x78, 0x07, 0x16, 0x25, 0x34, 0x43, 0x52, 0x61, 0x70,
0x7F, 0x7E, 0x7D, 0x7C, 0x7B, 0x7A, 0x79, 0x78, 0x07, 0x16, 0x25, 0x34, 0x43, 0x52, 0x61, 0x70
);
// broadcast 0x08 then blendd...
const __m256i shuffle_b = _mm256_set_epi32(
0x08080808, 0x08080808, 0x00000000, 0x00000000,
0x08080808, 0x08080808, 0x00000000, 0x00000000
);
for( uint8_t* end = &src[(length & ~31)]; src != end; src += 32){
__m256i r0,r1,r2,r3,r4;
unsigned int s0,s1;
r0 = _mm256_loadu_si256((__m256i *)src); // asrc
// detect spaces
r1 = _mm256_cmpeq_epi8(_mm256_shuffle_epi8(lut_cntrl2, r0), r0);
r2 = _mm256_sad_epu8(zero, r1);
s0 = (unsigned)_mm256_movemask_epi8(r1);
r1 = _mm256_andnot_si256(r1, permutation_mask);
r1 = _mm256_sad_epu8(r1, invert_mask); // index_bitmap[0:5], low32_spaces_count[7:15]
r2 = _mm256_shuffle_epi8(r2, zero);
r2 = _mm256_sub_epi8(shuffle_a, r2); // add space cnt of low qword
s0 = ~s0;
r3 = _mm256_slli_epi64(r1, 29); // move top part of index_bitmap to high dword
r4 = _mm256_srli_epi64(r1, 7); // number of spaces in low dword
r4 = _mm256_shuffle_epi8(r4, shuffle_b);
r1 = _mm256_or_si256(r1, r3);
r1 = _mm256_permutevar8x32_epi32(lut, r1);
s1 = _mm_popcnt_u32(s0);
r4 = _mm256_add_epi8(r4, shuffle_a);
s0 = s0 & 0xFFFF; // isolate low oword
r2 = _mm256_shuffle_epi8(r4, r2);
s0 = _mm_popcnt_u32(s0);
r2 = _mm256_max_epu8(r2, r4); // pin low qword bytes
r1 = _mm256_xor_si256(r1, fixup);
r1 = _mm256_shuffle_epi8(r1, r2); // complete shuffle mask
r0 = _mm256_shuffle_epi8(r0, r1); // despace!
_mm_storeu_si128((__m128i*)dst, _mm256_castsi256_si128(r0));
_mm_storeu_si128((__m128i*)&dst[s0], _mm256_extracti128_si256(r0,1));
dst += s1;
}
// tail loop
length &= 31;
if (length != 0) {
const uint64_t bitmap = 0xFFFFFFFEFFFFC1FF;
do {
uint64_t c = *src++;
*dst = (uint8_t)c;
dst += ((bitmap >> c) & 1) | ((c + 0xC0) >> 8);
} while (--length);
}
return (size_t)(dst - ((uint8_t*)dst_void));
}
For posterity, the 1 KiB version (generating the table is left as an exercise for the reader).
static const uint64_t table[128] __attribute__((aligned(64))) = {
0x0706050403020100, 0x0007060504030201, ..., 0x0605040302010700, 0x0605040302010007
};
const __m128i mask_01 = _mm_set1_epi8( 0x01 );
__m128i vector0 = _mm_loadu_si128((__m128i*)src);
__m128i vector1 = _mm_shuffle_epi32( vector0, 0x0E );
__m128i bytemask0 = _mm_cmpeq_epi8( ???, vector0); // detect bytes to omit
uint32_t bitmask0 = _mm_movemask_epi8(bytemask0) & 0x7F7F;
__m128i hsum = _mm_sad_epu8(_mm_add_epi8(bytemask0, mask_01), _mm_setzero_si128());
vector0 = _mm_shuffle_epi8(vector0, _mm_loadl_epi64((__m128i*) &table[(uint8_t)bitmask0]));
_mm_storel_epi64((__m128i*)dst, vector0);
dst += (uint32_t)_mm_cvtsi128_si32(hsum);
vector1 = _mm_shuffle_epi8(vector1, _mm_loadl_epi64((__m128i*) &table[bitmask0 >> 8]));
_mm_storel_epi64((__m128i*)dst, vector1);
dst += (uint32_t)_mm_cvtsi128_si32(_mm_unpackhi_epi64(hsum, hsum));
https://github.com/InstLatx64/AVX512_VPCOMPRESSB_Emu has some benchmarks.
If one is willing to use BMI2 available on haswell and later, one can use pdep to first compress unwanted nibbles out from uint64_t, and then use pext to scatter the result to shuffle mask.
// Step 1 -- replicate mask to nibbles
uint64_t change4 = pdep(change1, 0x1111111111111111ULL) * 0x0F;
// Step 2 -- extract index from array of nibbles
uint64_t indices = pext(0xfedcba09876543210, change4);
// Step 3 -- interleave nibbles to octects
uint64_t high = pdep(indices >> 32ULL,0x0F0F0F0F0F0F0F0F);
uint64_t low = pdep(indices, 0x0F0F0F0F0F0F0F0FULL);
// Step 4 -- use these two masks to compress pSrc
__m128i compressed = _mm_shuffle_epi8(pSrc, _mm_set_epi64(high, low));
// Step 5 -- store 16 bytes unaligned
_mm_storeu_si128(pDst, compressed);
// Step 6 -- increment target pointer
pDst += __mm_popcnt(change1);
Also other variants (based on cumulative sum or sorting the 'X's (or zero bits) out from XX23456789abXXef will first require some technique to spread the bits from uint16_t evenly to __m128i (i.e. reverse of movemask_epi8).
The 64k entry LUT can however be split to top and bottom parts:
int c = change1 & 0xff;
int p = __popcount(c);
uint64_t a = LUT256[c]; // low part of index
uint64_t b = LUT256[change1 >> 8]; // top part of index
b += addlut9[p]; // 0x0101010101010101 * p
// Then must concatenate b|a at pth position of 'a'
if (p < 8)
{
a |= b << (8*(8-p));
b >>= 8*p;
}
__m128i d = _mm_shuffle_epi8(_mm_loadu_si128(pSrc),_mm_set1_epi64(b,a));
// and continue with steps 5 and 6 as before
I am newbie to Pic Programming, I am using MPLAb & Hitech compiler to execute above code. I am trying to Interface PIC16F886 with ISL12022M Real time I2C device. i copied code example written for DS1307 interface with 16F887A PIC. I have capable to inteface Basic functionality with above . In below code While write into ISL12022M o could able to see data what i have send in memory register But as when Trying to read rtc time i could able to read last memory write value From SSPBUF. let me know any error in below code.
once I2c read value should be displayed on 4 digit seven segment display.
I think I am doing Misatake in this part. while Reading data i m just sending address so whatever last written in address it displaying.
#include <htc.h>
#include <stdio.h>
#include<pic.h>
#include<stdint.h>
#define _XTAL_FREQ 40000000
unsigned int i=0;
unsigned int k=0;
unsigned int count;
#define Pulse RA5
#define LED RC0
#define LED1 RC2
#define CONTROLREG 0xFF
#define SDA RC4 // Data pin for i2c
#define SCK RC3 // Clock pin for i2c
#define SDA_DIR TRISC4 // Data pin direction
#define SCK_DIR TRISC3 // Clock pin direction
#define DP RA4
#define I2C_SPEED 100 // kbps
unsigned short int cnt, num,Dgt=0;;
unsigned short int temp1,temp2,temp3;
unsigned short sec;
unsigned short min;
unsigned short hour;
unsigned short date;
unsigned short month;
unsigned short year;
unsigned short day;
unsigned short int temp=0;
unsigned short r_data;
#define Seg1 0x01
#define Seg2 0x02
#define Seg3 0x04
#define Seg4 0x08
void SetSeg(unsigned short data, unsigned short segno)
{
switch(data)
{
case 0: PORTB = 0x3F; break;
case 1: PORTB = 0x06; break;
case 2: PORTB = 0x5B; break;
case 3: PORTB = 0x4F; break;
case 4: PORTB = 0x66; break;
case 5: PORTB = 0x6D; break;
case 6: PORTB = 0x7D; break;
case 7: PORTB = 0x07; break;
case 8: PORTB = 0x7F; break;
case 9: PORTB = 0x6F; break;
default : PORTB = 0X00; break;
}
if(segno==1)
{
PORTA = Seg4;
}
if(segno==2)
{
PORTA = Seg3;
}
if(segno==3)
{
PORTA = Seg2;
}
if(segno==4)
{
PORTA = Seg1;
}
}
void Delay(int k)
{
int j;
for(j=0;j<k;j++);
}
void InitI2C(void)
{
SDA_DIR = 1; // Make SDA and
SCK_DIR =0; // SCK pins input
SSPCON = 0b00111000; //enables port for i2c
SSPCON2 = 0b00000000;
SSPADD = 10; // 100KHz = 8MHz/4(SSPADD+1)
// SSPSTAT = 0b11000000; // Slew rate disabled
}
void i2c_waitForIdle(void)
{
unsigned int i2ctimeout;
while(1)
{
i2ctimeout++;
if(i2ctimeout > 10)
{
i2ctimeout = 0;
return;
}
}
}
void I2C_Start(void)
{
SEN = 1; // Send start bit
i2c_waitForIdle();
/* while(!SSPIF); // Wait for it to complete
SSPIF = 0; // Clear the flag bit*/
}
void I2C_ReStart(void)
{
RSEN = 1; // Send Restart bit
i2c_waitForIdle();
/* while(!SSPIF); // Wait for it to complete
SSPIF = 0; // Clear the flag bit
while(RSEN==1);*/
}
void I2C_Stop(void)
{
PEN = 1; // Send stop bit
i2c_waitForIdle();
}
void I2C_Send_ACK(void)
{
ACKDT = 0; // 0 means ACK
ACKEN = 1; // Send ACKDT value
i2c_waitForIdle();
}
void I2C_Send_NACK(void)
{
ACKDT = 1; // 1 means NACK
ACKEN = 1; // Send ACKDT value
i2c_waitForIdle();
}
unsigned char I2C_Write( unsigned char i2cWriteData )
{
i2c_waitForIdle();
SSPBUF = i2cWriteData;
return (!ACKSTAT); // function returns '1'
}
int I2C_Read( unsigned char ack )
{
unsigned char i2cReadData;
//unsigned int i2cReadData;
i2c_waitForIdle();
RCEN = 1;
SDA=1;
SCK=1;
i2c_waitForIdle();
i2cReadData = SSPBUF;
SCK=0;
i2c_waitForIdle();
SCK=1;
if(ack)
{
ACKDT = 0;
}
else
{
ACKDT = 1;
}
ACKEN = 1; // send acknowledge sequence
return( i2cReadData );
}
unsigned int bcdtodecimal(unsigned int bcd)
{
unsigned int decimal;
decimal = (((bcd & 0xF0) >> 4) * 10) + (bcd & 0x0F);
return decimal;
}
void Init_ISL12022M(void)
{
I2C_Start(); // Start I2C communication
I2C_Write(0XD0); //Write Device Address
I2C_Write(0X08); //
I2C_Write(0X41); // Write 0x00 to Control register to disable SQW-Out
I2C_Stop(); // Stop I2C communication after initilizing
}
unsigned int Write_ISL12022M(unsigned short address, unsigned short w_data)
{
I2C_Start(); // Start I2C communication
I2C_Write(0XD0);
I2C_Write(address); //write address to write data
I2C_Write(w_data); //write data into hexadecimal
I2C_Stop();//stop I2C communication
return(w_data);
}
unsigned short Read_ISL12022M(unsigned short address)
{
I2C_Start();
I2C_Write(address); //address 0x68 followed by direction bit (0 for write, 1 for read) 0x68 followed by 0 --> 0xD0
I2C_Write(address);
I2C_ReStart();
I2C_Write(0xD1); //0x68 followed by 1 --> 0xD1
r_data=I2C_Read(0);
I2C_Stop();
return(r_data);
}
void SetDateTime()
{
I2C_Start();
I2C_Write(0xD0);
I2C_Write(0x00);
sec= Write_ISL12022M(0X00, 12); //01 sec
min = Write_ISL12022M(0X01,52); //01 sec
hour = Write_ISL12022M(0X02,9); //01 sec
day= Write_ISL12022M(0X03,7); //01 sec
date = Write_ISL12022M(0X04, 29); //01 sec
month =Write_ISL12022M(0X05,07); //01 sec
year = Write_ISL12022M(0X06,17); //01 sec
I2C_Stop();
}
void RTC_GetDateTime()
{
I2C_Start(); // Start I2C communication
I2C_Send_ACK();
sec = I2C_Read(1); // read second and return Positive ACK
I2C_Send_ACK();
min = I2C_Read(1); // read minute and return Positive ACK
I2C_Send_ACK();
hour= I2C_Read(0); // read hour and return Negative/No ACK
I2C_Send_ACK();
day = I2C_Read(1); // read weekDay and return Positive ACK
I2C_Send_ACK();
date= I2C_Read(1); // read Date and return Positive ACK
I2C_Send_ACK();
month=I2C_Read(1); // read Month and return Positive ACK
I2C_Send_ACK();
year =I2C_Read(0); // read Year and return Negative/No ACK
I2C_Send_ACK();
I2C_Stop(); // Stop I2C communication after reading the Date
}
void interrupt isr(void)
{
if(TMR1IF==1)
{
TMR1H=0xF6; // Load the time value(0xBDC) for 100ms delay
TMR1L=0x18; //Timer1 Interrupt for 65000
TMR1IF=0; // Clear timer interrupt flag
Dgt++;
if(Dgt>=5)
{
Dgt=0;
LED=!LED;
}
}
}
void Timer1_Interrupt()
{
INTCON = 0b00000000;
PIE1=0b00000001;
PIR1=0x01;
TMR1H=0x0B;
TMR1L=0xDC;
T1CON=0x31;
}
void Init_Controller()
{
cnt=100;
TRISC=0b01000000; // Intialize INput & output pheripherals
TRISB=0b10000000;
PORTB = 0b00000000;
TRISA=0b0000000;
ADCON0 = 0b00000000;
ANSEL = 0b00000000;
Timer1_Interrupt();
}
void main(void)
{
Init_Controller();
/* GIE=1;
PEIE=1;
TMR1IE=1; */
InitI2C();
Init_ISL12022M();
SetDateTime();
while(1)
{
RTC_GetDateTime();
SetSeg(year/ 10,2);
SetSeg(year%10,1);
}
}
The lines like:
I2C_Write(0XD0); //Write Device Address
are not a valid device addresses. Use 0xDE (or 0xAE for User SRAM)
From the datasheet:
Following a start condition, the master must output a Slave Address Byte. The 7 MSBs are the device identifiers. These bits are “1101111” for the RTC registers and “1010111” for the User SRAM.
i am trying to Read an Voltage Level via a ADC0 of my ATmega8, because of querying a 1 Pin 4x4 Matrix Keypad. The Problem is everytime I apply a Voltage to the ADC higher than GND the Atmega is stopping to do his work. The PWM outputs are still working, but communication via i2c is impossible and the LCD is clear.
My wiring is simple, AREF & AVCC are set to 5V, GND is set to GND and PC0 is my Input. Is there anything I fail to Notice? Thank You for your help.
Here is my Code:
void Initialisierung(void)
{
char text [2];
lcd_init();
cli();
//### TWI
init_twi_slave(SLAVE_ADRESSE); //TWI als Slave mit Adresse slaveadr starten
sei();
lcd_setcursor( 0, 1 );
lcd_string(">Booting...");
lcd_setcursor( 0, 2 );
itoa (SLAVE_ADRESSE,text,16);
lcd_string("I2C Adress=0x");
lcd_string(text);
for (int Index=0; Index<85; ++Index) {
rxbuffer[Index] = 0x20;
}
rxbuffer[81]=0xFF;
rxbuffer[82]=0xFF;
rxbuffer[83]=0xFF;
rxbuffer[84]=0xFF;
}
//update LCD
void lcd_update(void){
for (int o=1;o<=4; o++)
for (int i=1; i<=20; i++){
lcd_setcursor( i-1, o );
lcd_data(rxbuffer[i+((o-1)*20)]);
}
}
An here is the main function:
int main(void)
{
DDRC &= ~(1 << PC0);
PORTC &= ~(1 << PC0);
Initialisierung();
DDRB = (1 << DDB1) | (1 << DDB2);
OCR1A = eeprom_read_word(&brightness); // PWM einstellen,
OCR1B = eeprom_read_word(&contrast);
ICR1 = 1000; // TOP-wert
TCCR1A = (1<<COM1A1) | (1<<COM1B1) | (1<<WGM11); // 2-Kanal "non-inverting"
TCCR1B = (1<<WGM13)|(1<<WGM12) | (1<<CS11);
//Initialize ADC
ADCSRA = (1<<ADEN) | (1<<ADPS2) | (1<<ADPS0);
ADMUX=0x00;
unsigned int adc_value=0; // Variable to hold ADC result
char text[2];
while(1)
{
ADCSRA |= (1<<ADSC); // Start conversion
while (ADCSRA & (1<<ADSC)); // wait for conversion to complete
adc_value = ADCW; //Store ADC value
itoa (adc_value,text,16);
lcd_setcursor( 0,4 );
lcd_string(text);
for (int Index=0; Index<85; ++Index) {
txbuffer[Index] = rxbuffer[Index];
}
uint16_t brightness_i2c=0;
uint16_t contrast_i2c=0;
brightness_i2c=(rxbuffer[81]<<8)|(rxbuffer[82]);
contrast_i2c=(rxbuffer[83]<<8)|(rxbuffer[84]);
if (rxbuffer[0]==1){
lcd_update();
rxbuffer[0]=4;
}else if(brightness_i2c!=eeprom_read_word(&brightness) && brightness_i2c!=0xFFFF){
eeprom_write_word(&brightness,brightness_i2c);
OCR1A = eeprom_read_word(&brightness);
}else if (contrast_i2c!=eeprom_read_word(&contrast) && contrast_i2c!=0xFFFF){
eeprom_write_word(&contrast,contrast_i2c);
OCR1B = eeprom_read_word(&contrast);
}else{
for (uint8_t i=0; i<50; i++) _delay_ms(10);
lcd_setcursor( 19, 4 );
lcd_data(0xFF);
for (uint8_t i=0; i<50; i++) _delay_ms(10);
lcd_setcursor( 19, 4 );
lcd_data(0x20);
}
}
}
I finally got it:
I setup the ADC with interrupts but not freerunning:
ADCSRA =(1<<ADEN)|(1<<ADPS2)|(1<<ADPS1)|(1<<ADIE)| (1<<ADPS0);
And call the ADC everytime at the end of my While loop:
ADCSRA |= (1<<ADSC);
Here is the Code for the ISR:
ISR(ADC_vect)
{
char text[5];
itoa (ADC,text,16);
lcd_setcursor( 0,4 );
lcd_string(text);
}
Thanks for your time ;)
I Want to compare the character recieved via RX pin of ATMEGA 8. WHy doesn't the comparison work?
int main()
{
DDRB = 0XFF;
UCSRB = (1<<RXEN);
UCSRC = (1<<URSEL)|(1<<UCSZ1)|(1<<UCSZ0);
UBRRL = 0X33;
char r;
while (1)
{
while(!(UCSRA&(1<<RXC)));
r = UDR;
if(r=='r') PORTB = 0XFF;
}
return 0;
}
Sample code for easy setting baud_rate
#define F_CPU 8000000UL // Chip CPU frequency here, prevents default 1MHz
#define USART_BAUDRATE 19200UL // Baud_rate here, baudrates: 300, 600, 1200, 2400, 4800, 9600, 19200, 38400, 57600, 115200, 230400, 460800, 921600
#define BAUD_PRESCALE (((F_CPU / (USART_BAUDRATE * 16UL))) - 1)
#include <avr/io.h>
int main(void) {
DDRB = 0XFF;
UBRRL = BAUD_PRESCALE; // baud to low byte of the UBRR register
UBRRH = (BAUD_PRESCALE >> 8); // baud to high byte of the UBRR register
UCSRB = (1<<RXEN);
UCSRC = (1<<URSEL)|(1<<UCSZ1)|(1<<UCSZ0);
char r;
while(1) {
//TODO:: Please write your application code
while(!(UCSRA&(1<<RXC)));
r = UDR;
if(r=='r') PORTB = 0XFF;
}
return 0;
}