Tool/software:
Hello,
I have created a circuit board using the exact same schematic as the BQ76942_2Layer_TestBoard circuit. What should be my first step to configure and wake up the BQ device? I want to query the Device Number by writing to address 0x0001 at device address 0x3E with an external MCU, and then read from address 0x40, but I am unable to get the Device Number value. Do I need to connect a battery pack first? What am I doing wrong and what should I do? Thank you in advance.
When we connect the battery, we see 25V on the Vbat pin and 36V on the CP1 pin of the BQ. However, there is no voltage on the REGs. Additionally, when we try to connect to the SCL and SDA pins of the BQ and run this code, we cannot establish communication, and it does not return the Device_Number to us.
#define DEVICE_NUMBER 0x0001
Hi Tayyar,
Pulling TS2 low momentarily and pulling it to ground continuously should have the same effect. However, having TS2 shorted continuously will prevent the device from ever entering SHUTDOWN mode.
A couple questions:
1. How are you pulling TS2 to ground? You should pull it ground through a 10kΩ resistor like below:
2. Can you check the REG18 voltage? The voltage should be ~1.8V if the device is on. This is will double check to make sure the device is on.
Best regards,
Thomas Rainey
1)I continuously read the device number with the command and reset it with the reset button of the MCU and make the command go to BQ again, after doing this about 7 times, the communication breaks and I cannot get the device number.
2)I send the Sleep_Disable command using this function
Hello Tayyar,
I need a logic analyzer capture with the SCL and SDA lines. Similar to this:
This help with determining what is being sent and received from the device.
Best regards,
Thomas Rainey
I will transmit the Logic analyzer image, in fact, basically our problem is that when we read Battery_Status, it returns 0x8001 and we understand that the device is in sleep mode. Apart from this, when we perform voltage and current reading operations, we can read cell voltages, stack voltage correctly, but we read a very high value (65A) in current reading, you can see the value we read from the image and the codes we wrote to read current.
