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LOW-COST DOUBLE LI-ION BATTERY CHARGER USING ST6255C/ST6265C MCU

Figure 9. State Diagram (3) – Heat State Transitions

2.4.4 Slot Monitor Flowchart

In the software, slot states are updated by a subroutine called “slot monitor”. Using a subrou-

tine is possible because the front and rear slot state diagrams are almost identical.

Slot state is stored in a one-byte variable, coded in a way that facilitates decoding the condi-

tion tree:

IDLE

EQU

00000001b

HEAT

EQU

10100000b

FAIL

EQU

11000001b

EXP

EQU

11010001b

SAT

EQU

11011001b

TRI

EQU

11100001b

FAST

EQU

11110000b

CV_D

EQU

11111000b

CI

EQU

11111100b

CV_U

EQU

11111110b

Decoding starts from the most significant bit. The least significant bit indicates front slot priority

request (1 = no request). When the slot enters HEAT state, this bit is modified to be the same

CI

CV_D

CV_U

TRI

FAIL

HEAT

IDLE

no overheat

Original

state

EXP

Original

state saved

overheat

SAT

FAST