TC1796
System Units (Vol. 1 of 2)
Introduction
User’s Manual
1-4
V2.0, 2007-07
Intro, V2.0
1.1.4
Register Access Modes
Read and write access to registers and memory locations are sometimes restricted. In
memory and register access tables, the terms as defined in
are used.
Table 1-2
Access Terms
Symbol
Description
U
Access Mode: Access permitted in User Mode 0 or 1.
Reset Value: Value or bit is not changed by a reset operation.
SV
Access permitted in Supervisor Mode.
R
Read-only register.
32
Only 32-bit word accesses are permitted to this register/address range.
E
Endinit-protected register/address.
PW
Password-protected register/address.
NC
No change, indicated register is not changed.
BE
Indicates that an access to this address range generates a Bus Error.
nBE
Indicates that no Bus Error is generated when accessing this address
range, even though it is either an access to an undefined address or the
access does not follow the given rules.
nE
Indicates that no Error is generated when accessing this address or
address range, even though the access is to an undefined address or
address range. True for CPU accesses (MTCR/MFCR) to undefined
addresses in the CSFR range.
X
Undefined value or bit.