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Memory sizes – HP Q153090901 User Manual

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Memory sizes

Main buffer memory:
The Main Buffer memory is 128 MB.

Areas of the Main Buffer memory are used by the firmware. These should not be written to and

should not be expected to retain values that are written to them. Any Write and Read Buffer tests

can be performed while the drive is idle. If the drive is reading or writing, the data being written or

read can be corrupted.

Since the drive has more than 16 MB of Main Buffer memory, additional buffer IDs have been

defined to allow the whole buffer to be accessed in 16 MB segments. These are defined as follows:

Main processor memory:
Not all the Processor memory space is accessible. Take care when writing to any addresses within

this buffer.

SCSI burst buffer:
Addressable range from 00000h through 3F8000h.

PCA EEPROM:
The write range is limited to 500h bytes, starting at 100h (TapeTools area).

Buffer ID

Address

20h

00000000h + Buffer Offset (same as Buffer ID 00h)

21h

01000000h + Buffer Offset (that is, +16 MB)

22h

02000000h + Buffer Offset (that is, +32 MB)

23h

03000000h + Buffer Offset (that is, +48 MB)

24h

04000000h + Buffer Offset (that is, +64 MB)

25h

05000000h + Buffer Offset (that is, +80 MB)

26h

06000000h + Buffer Offset (that is, +96 MB)

27h

07000000h + Buffer Offset (that is, +112 MB)