Chapter 7: C790 Bus/G-Bus Bridge
TX7901 User’s Manual (Rev. 6.30T – Nov, 2001)
7-8
7.6.3
C790 Bus Status Register
The Bus Status Register reports the status of the C790 Bus. The ERR bit is set when the
bridge is writing to main memory, then a C790 bus error occurs. The C790 can clear this bit
by writing a “0”. Writing a “1” is ignored. The fields of the Bus Status Register are detailed
below and in Table 7-4. Note that read errors are detected by the transaction originator.
63
32
0
32
31
1
0
0
E
R
R
31
1
Table 7-4 C790 Bus Status Register Fields
Bit(s)
Field
R/W
Description
Initial Value
63:1
–
R/O
Reserved. Must be written as zeroes,
and returns zeroes when read.
0
0
ERR
R/W
C790 Bus Error
1: Bus Error occurred
0: No bus error
Error is generated when ERR = 1.
Writes "0" when cleared. Writing "1" to
this bit has no effect.
This bit is not set during reads.
Notification is just sent to the Master.
0
Summary of Contents for TMPR7901
Page 1: ...TX System RISC TX79 Family TMPR7901 Symmetric 2 way superscalar 64 bit CPU ...
Page 14: ...Handling Precautions ...
Page 15: ......
Page 17: ...1 Using Toshiba Semiconductors Safely 1 2 ...
Page 41: ...4 Precautions and Usage Considerations 4 2 ...
Page 42: ...TX7901 User s Manual Rev 6 30T November 2001 DOCUMENT NUMBER M 99 00004 07 ...
Page 43: ......
Page 259: ...Chapter 13 Removed TX7901 User s Manual Rev 6 30T Nov 2001 13 1 13 Removed ...
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