Register Conventions
C55x DSP/BIOS Register Usage
B-3
BK03, BK47, BKC
Circular Buffer Size Registers
H
BRC0, BRC1
Block-repeat counters
H
BRS1
BRC1 save register
H
BSA01, BSA23,
BSA45, BSA67, BSAC
Circular Buffer Start Address Regis-
ters
H
(X)CDP
Coefficient Data Pointer
H
CFCT
Control-flow context register
H,T
CSR
Computed Single Repeat
H
DBIER0, DBIER1
Debug Interrupt Enable Registers
G
DSP/BIOS does not touch these
registers.
(X)DP
Data Page Register
H,T
IER0, IER1
Interrupt Enable Registers
I
Modified by interrupt handlers,
and may not be fully restored
upon return.
IFR0, IFR1
Interrupt Flag Registers
G
Initialized by DSP/BIOS at boot
time, untouched thereafter.
IVPD, IVPH
Interrupt Vector Table Pointers
G
Initialized by DSP/BIOS at boot
time, untouched thereafter.
PC
Program Counter
H, T
RPTC
Single Repeat Counter
H
RSA0, RSA1
Block-repeat start address registers
H
REA0, REA1
Block-repeat end address registers
H
RETA
Return Address Register
H,T
(X)SP
Stack Pointer
H,T
Changed to ISR SP during HWI
execution, restored upon return.
(X)SSP
System Stack Pointer
H,T
Changed to ISR SSP during HWI
execution, restored upon return.
T0, T1
Temporary Registers
H,T
T2, T3
Temporary Registers
T
These "child" registers are pre-
sumed to be saved by an HWI
that uses them.
TRN0, TRN1
Transition Registers
H
Register
Register Name
Type
Notes