Rainbow Electronics DS2770 - Manual (Page 13)

DS2770
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MEMORY MAP Figure 11
ADDRESS (HEX) DESCRIPTION R/W
00 Reserved
01 Status Register R**
02 Elapsed Time Register MSB R/W
03 Elapsed Time Register LSB R/W
04 to 05 Reserved
06 Charge Time Register R/W
07 EEPROM Register R/W
08 to 0B Reserved
0C Voltage Register MSB R
0D Voltage Register LSB R
0E Current Register MSB R
0F Current Register LSB R
10 Accumulated Current Register MSB R/W
11 Accumulated Current Register LSB R/W
12 to 17 Reserved
18 Temperature Register MSB R
19 Temperature Register LSB R
1A to 1F Reserved
20 to 2F Lockable EEPROM Block 0 R/W*
30 to 3F Lockable EEPROM Block 1
(31 = Status Register Initialization)
(32 to 33 = Current Offset Register)
(34 = Charge Time Register Initialization) R/W*
40 to 47 Lockable EEPROM Block 2 R/W*
48 to 7F Reserved
80 to 8F General-Purpose SRAM R/W
90 to FF Reserved
* The lockable EEPROM address locations 20h through 47h are writeable until locked by using the Lock
function command [6Axxh], after which it is read only.
** The Status Register bits are read only. However, writing any byte value to the Status Register is
required to clear a previous charge completion condition flagged with both CSTAT1, CSTAT0 bits set.
STATUS REGISTER
The default values for the Status Register are stored in lockable EEPROM in the corresponding bits of
address 31h. These values in address location 31h are supplied directly to the Status Register (not from
shadow RAM) on either a device power-up or upon execution of the Refresh command. Changes to the
Status Register bits must be made to the EEPROM location 31h, and then use the Refresh command to
recall the changes to the Status Register. Figure 12 shows the format of the Status Register. The function
of each bit is described in detail in the following paragraphs.