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UDG−04099

21−V pulse applied to

PROG pin for 50 ms

Host enables E2PROM

programming mode. Write data

0xDD to address 0x6E

Host writes data in addresses

0x76 − 0x7F

Host reads data

address 0x76

Write data 0x00 to

address 0x6E

Programmed

0x7F?

Host increments

address and reads

No

Yes

Communicating With the bq27010 (HDQ interface)

bq27010, bq27210

SLUS707B – APRIL 2006 – REVISED JANUARY 2007

Figure 6. EEPROM Programming Flow

It is not required that addresses 0x76 — 0x7F be programmed at the same time or in any particular order. The

programming method illustrated in Figure 6 can be used to program any of the bytes as long as the sequence of

Enable, Write, Read, Apply Programming Pulse, and Disable is followed.

The bqJUNIOR must have a full reset to force the updated EEPROM values into RAM. A full reset will occur

after a POR if RAM data is corrupted (failed checksum), or a full-reset command may be sent using the CTRL

and MODE registers.

The bq27010 includes a single-wire HDQ serial data interface. Host processors, configured for either polled or

interrupt processing, can use the interface to access various bq27010 registers. The HDQ pin is an open-drain

device, which requires an external pullup resistor. The interface uses a command-based protocol, where the

host processor sends a command byte to the bq27010. The command directs the bq27010 either to store the

next eight bits of data received to a register specified by the command byte or to output the eight bits of data

from a register specified by the command byte.

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