Branch Source Register (Brsr) - Hitachi SH7709S Hardware Manual

7.2.11

Branch Source Register (BRSR)

BRSR is a 32-bit read register. BRSR stores the last fetched address before branch and the pointer
(3 bits) which indicates the number of cycles from fetch to execution for the last executed
instruction. BRSR has the flag bit that is set to 1 when branch occurs. This flag bit is cleared to 0,
when BRSR is read and also initialized by power-on resets or manual resets. Other bits are not
initialized by reset. Eight BRSR registers have queue structure and a stored register is shifted
every branch.
Bit:
SVF
Initial value:
R/W:
Bit:
BSA23
Initial value:
R/W:
Bit:
BSA15
Initial value:
R/W:
Bit:
BSA7
Initial value:
R/W:
Note: * Undefined value
Bit 31—BRSR Valid Flag (SVF): Indicates whether the address and the pointer by which the
branch source address can be calculated. When a branch source address is fetched, this flag is set
to 1. This flag is cleared to 0 in reading BRSR.
Bit 31: SVF Description
0 The value of BRSR register is invalid
1 The value of BRSR register is valid
31 30 29
PID2 PID1
0
* *
R R R
23 22 21
BSA22 BSA21
* * *
R R R
15 14 13
BSA14 BSA13
* * *
R R R
7 6 5
BSA6 BSA5
* * *
R R R
28 27 26
PID0 BSA27 BSA26
* * *
R R R
20 19 18
BSA20 BSA19 BSA18
* * *
R R R
12 11 10
BSA12 BSA11 BSA10
* * *
R R R
4 3 2
BSA4 BSA3 BSA2
* * *
R R R
25 24
BSA25 BSA24
* *
R R
17 16
BSA17 BSA16
* *
R R
9 8
BSA9 BSA8
* *
R R
1 0
BSA1 BSA0
* *
R R
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