DS2438 in verifone POS battery

Projects General Guidance
1

Hello all.

I have some verifone batteries and all batteries are new and good.
In some batteries with 8v of charge (99%) they are showed 0% in POS.

I need to write an Arduino project to "Reset" the circuit protection of this battery. I discover that this battery have a DS2438 from Dallas and the battery have 4 pins: + , DQ, ID, -...

Anybody knows how i have to build this circuit and how i read the battery protection circuit? I´m trying 1-wire library, some examples but without success.
I´m try with 4.7kohm pull-up in DQ port of battery but i made something wrong.

Can anybody help me? Thanks so much

2

The DS2438 has a DQ pin for OneWire. As shown in Figure 8 you must provide a 4.7K pull-up resistor for the OneWire bus. Are you able to get any data from the chip? Did you try the Read ROM command (0x33) to read out the chip serial number?