Quantum ATL SuperLoader ATL, User Manual

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Chapter 3 Media Changer Commands
Read Buffer Command (3Ch)
Quantum ATL SuperLoader Software Interface Guide 123
Data Mode (0010b)
3
LTO Only: In this mode, the DATA IN phase contains only buffer
data.The buffer ID must be set to 0. The buffer offset must be less
than the size of the buffer.
Descriptor Mode
(0011b)
3
In this mode, a maximum of four bytes of READ BUFFER
descriptor information is returned. The device returns the
descriptor information for the buffer specified by the Buffer ID. In
this mode, the device does not reject the invalid Buffer IDs with a
CHECK CONDITION status, but returns all zeros in the READ
BUFFER descriptor.
Figure 61 Read Buffer
Descriptor
Read Data from
Echo Buffer
(1010b)
3
In this mode the device transfers data to the application client from
the Echo Buffer. The Echo Buffer will transfer the same data as
when the WRITE BUFFER command with the mode field set to
Echo Buffer was issued. The Buffer ID and Buffer Offset fields are
ignored in this mode.
Bit
Byte
7 6 5 4 3 2 1 0
0
Offset Boundaries (0h)
1 - 3
(MSB)
Buffer Capacity
(LSB)