zaplakkies
commented
2 months ago Ive had it a few times where it would just crash directly after reading a point as well. This made me look at the filter caps, which were not a problem. Then I took a look at the library in a bit more detail. After I replaced the two lines in write_bit from DIRECT_WRITE_HIGH(reg, mask); to DIRECT_MODE_INPUT(reg, mask); all problems seem to have vanished. Making it an input automatically makes it high without the risk of shorting the output pin from vcc to gnd. It does not make too much sense as I cant the the ds1990 pulling the line low when the master is pulling it high. It does seem to work though so there is that.
Description
Im having a problem where if I read an id point, which reads fine btw, after the unit goes to sleep it wont wake up. If I short the line to wake up the unit it tries to find a point and when it fails it goes to sleep. ie the wakeup from sleep works fine as long as I don't read a point successfully.
Steps To Reproduce Problem
using an atmega328pb put an led on pin25 and the dallas line with the appropriate pull up resistor on pin32 (INT0). Use the code below. shorting the line wakes the unit up momentarily and then it goes to sleep. This can be done multiple times without problem. Put a DS1990 on the line and it will read the point, then go to sleep. Now you cannot wake the unit up
Hardware & Software
Board: Custom board with the bare minimum using an atmega328pb Shields / modules used : none Arduino IDE version : not using arduino ide using VScode Version info & package name (from Tools > Boards > Board Manager): 2.3.7 Operating system & version: Linux Ubuntu 23.04
Arduino Sketch
include
include <avr/io.h>
include <avr/sleep.h>
include <avr/interrupt.h>
include
include <avr/power.h>
include <avr/wdt.h>
include
define LED 16 // pin25
define TPout 2 // pin32
byte addr[8]; byte rty; boolean issame; boolean shorted = false;
OneWire ds(2);
volatile bool wokeUp = false;
//// Sleep sections //// void wakeUpInterrupt() { wokeUp = true; } void sleepNow() { set_sleep_mode(SLEEP_MODE_PWR_DOWN); // Choose the lowest power mode
sleep_enable(); sei(); // Enable interrupts to wake up from sleep digitalWrite(LED, LOW); // Enter sleep mode sleep_cpu(); // The program will continue from here when the microcontroller wakes up sleep_disable(); }
void setup() { // initialize digital pin LED_BUILTIN as an output. Serial.begin(9600); // init the leds to be off pinMode(LED, OUTPUT); pinMode(TPout, INPUT); digitalWrite(LED, LOW);
attachInterrupt(digitalPinToInterrupt(TPout), wakeUpInterrupt, CHANGE); Serial.println("end of setup"); sleepNow(); }
void loop() { if (wokeUp) { Serial.println("start of loop"); rty = 10; while (rty != 0) { // start retry loop rty--; pinMode(TPout, INPUT); delay(10); ds.reset_search(); if (ds.search(addr)) { digitalWrite(LED, HIGH); Serial.print("Recorded point, "); Serial.print(addr[3],HEX); Serial.print(addr[2],HEX); Serial.println(addr[1],HEX); delay(100); rty = 0; } } wokeUp = false; Serial.println("end of loop"); delay(100); sleepNow(); }
}