Fujitsu FR81S User Manual
CHAPTER 39: RAMECC
4. Registers
FUJITSU SEMICONDUCTOR LIMITED
CHAPTER : RAMECC
FUJITSU SEMICONDUCTOR CONFIDENTIAL
14
4.7. Double-bit ECC Error Address Register
BACKUP-RAM : DEEARA
The bit configuration of the double-bit ECC error address register BACKUP-RAM is shown.
When the double-bit error detection is performed during the ECC check of Backup-RAM, this register
maintains the address at which it occurred.
DEEARA : Address 3002
H
(Access: Byte, Half-word, Word)
bit15
bit14
bit13
bit12
bit11
bit10
bit9
bit8
Reserved
D10
D9
D8
Initial value
0
0
0
0
0
0
0
0
Attribute R0,W0
R0,W0
R0,W0
R0,W0
R0,W0
R,WX
R,WX
R,WX
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
D7
D6
D5
D4
D3
D2
D1
D0
Initial value
0
0
0
0
0
0
0
0
Attribute R,WX
R,WX
R,WX
R,WX
R,WX
R,WX
R,WX
R,WX
[bit15 to bit11] Reserved
Always write "0" to these bits.
[bit10 to bit0] D10 to D0 : Double-bit error occurrence address bits
When double-bit error detection is performed during the ECC check, these bits maintain the address at
which it occurred.
If the event above is further detected when a value has already been set to these bits, the original value is
maintained without overwriting these bits.
Note:
The address above is offset in words. Calculate the absolute address by adding the lower 2 bits to the offset
address mentioned above, and then adding the base address of Backup-RAM.
(Absolute address) = (0000_4000
H
) + (Offset indicated by DEEARX + 2b’00)
MB91520 Series
MN705-00010-1v0-E
1305