MPC563XM Reference Manual, Rev. 1
872
Freescale Semiconductor
Preliminary—Subject to Change Without Notice
23.4.8.1.3
ERT1 and ERT2 Registers
ERT1/2 registers are 24-bit wide and can be used as source or destination in arithmetic/logical operations.
ERT1/2 are the only source for channel’s match registers write (see
Section 23.4.9.3.5, “Write Channel
”). ERT1 can also be the source for UDCM write.
When a thread starts to be executed, ERT1 and ERT2 are loaded with a copy of Capture1 and Capture2
registers respectively. ERT1/2 can be used to receive a copy of Match1 and Match2 registers. ERT1/2 are
the only destination of Match1/2 read operation (see
Section , “Special T4ABS Source Operation: Read
”).
ERT1 and ERT2 also receive a copy of Capture1 and Capture2 registers when CHAN register is written
(see
Section 23.4.8.1.8, “CHAN Register
”). For more information about Capture and Match registers see
Section , “Match1 and Match2 Registers
Section , “Capture1 and Capture2 Registers
23.4.8.1.4
SR register - Shift Register
SR is a 24-bit wide register that can be used as source and destination register for arithmetic/logical
operations. SR can shift right its contents by 1 bit at time and, at the same time, receive in its bit 23 the lost
bit of a shift-right operation in post-ALU shifter (
Section 23.4.8.2, “ALU and Post-ALU Shifter
”),
allowing SR to be used to perform 48-bit shift right (see
Section 23.4.9.2.6, “Shift Operations
”).
23.4.8.1.5
MACH and MACL Registers
Both MACH and MACL are 24-bit registers, part of MAC/Divide unit (see
used as source and destination in most arithmetic/logic operations. When multiply or divide operations are
used (multiply-accumulate included), MACH and MACL have special purpose and some restrictions
apply, see
Section 23.4.8.3, “MAC and Divide Unit (MDU)
” for more information.
23.4.8.1.6
LINK Register
Link Register is an 8-bit wide register and can be used only as destination in arithmetic operations. LINK
is a write-only command register, which precludes its use as a source register for ALU operations. When
LINK register is written, it issues a service request for the channel number and eTPU engine equal to the
number written in LINK register (see
Section 23.4.1, “Functions and Threads
” and
” for information about Link Service Request).
23.4.8.1.7
RAR Register
RAR is a 14-bit register and can be used as source and destination in arithmetic operations. RAR also
receives the contents of PC register when a subroutine call is executed. The contents of RAR register is
loaded into PC when a return from subroutine is executed. RAR is loaded with value 0x3FFF during TST.
For more information about subroutine call and return see
Section 23.4.9.4.2, “Branch Operations
Section 23.4.9.4.4, “Return From Subroutine
” respectively.
23.4.8.1.8
CHAN Register
CHAN is a 5-bit register that can be used as source and destination in arithmetic operations. The contents
of CHAN register affects the execution of many channel-related microinstructions, because its number