Instruction Decoding
MSC8113 Reference Manual, Rev. 0
Freescale Semiconductor
18-5
18.3 Instruction Decoding
The MSC8113 includes the three mandatory public instructions EXTEST, SAMPLE/PRELOAD,
and BYPASS and also supports the optional CLAMP and HIGHZ instructions defined by IEEE
Std. 1149.1. The following public instructions perform key functions:
ENABLE_EONCE enables the JTAG port to communicate with the EOnCE circuitry.
DEBUG_REQUEST enables the JTAG port to force the MSC8113 into Debug mode.
CHOOSE_EONCE allows the operation of multiple EOnCE devices. This instruction
should always execute before the first ENABLE_EONCE instruction and should shift a 1
to the SC140 EOnCE module choose cells for each module that you want to enable. Since
there are three internal EOnCE modules, you must shift 4 bits to the choose cells. For
details, see Section 18.4.
The MSC8113 includes a 5-bit instruction register without parity, consisting of a shift register
with five parallel outputs. Data is transferred from the shift register to the parallel outputs during
the
UPDATE
-
IR
controller state. The five bits decode the ten unique instructions listed in Table
18-3Instruction Decoding, on page 18>-6. All other encoding, with the exception of the
manufacturer’s private instructions, is reserved for future enhancements and is decoded as
BYPASS.
The parallel output of the Instruction Register is reset to 0b00010 in the test-logic-reset controller
state, which is equivalent to the IDCODE instruction. During the
CAPTURE
-
IR
controller state, the
parallel inputs to the instruction shift register are loaded with the code 01 in the least significant
bits, as required by the standard. The most significant bits are loaded with the values upd_ack,
cores1, cores0, as shown in Table 18-2 and Figure 18-3. Two bits of the GPR are configured to
select an SC140 core, whose status is output from the multiplexer. Therefore, the status of all
SC140 cores can be viewed serially by updating the GPR between each SC140 core status
reading. Alternatively, all three SC140 cores can be viewed simultaneously from the PIREG.
For
details on core states, refer to the SC140 DSP Core Reference Manual.
Table 18-2. Instruction Register Capture and SC140 Core Status Values
Name/bits
Description
Settings
upd_ack
4
Update Acknowledge
Indicates whether the selected SC140 EOnCE module
has executed the last instruction dispatched to it
0
EOnCE module has executed the last instruction
dispatched to it.
1
EOnCE module has not executed the last
instruction dispatched to it.
cores[1–0]
3–2
Core Status
Reflects the status of the selected SC140 core
00 Core is executing instructions.
01 Core is in WAIT or STOP mode.
10 Core is waiting for bus.
11 Core is in debug mode.
—
1–0
Contains value required by the JTAG standard
Read-only
Summary of Contents for MSC8113
Page 1: ...MSC8113 Reference Manual Tri Core 16 Bit Digital Signal Processor MSC8113RM Rev 0 May 2008 ...
Page 20: ...MSC8113 Reference Manual Rev 0 xx Freescale Semiconductor Contents ...
Page 28: ...MSC8113 Reference Manual Rev 0 xxviii Freescale Semiconductor ...
Page 56: ...MSC8113 Reference Manual Rev 0 1 28 Freescale Semiconductor MSC8113 Overview ...
Page 76: ...MSC8113 Reference Manual Rev 0 2 20 Freescale Semiconductor SC140 Core Overview ...
Page 134: ...MSC8113 Reference Manual Rev 0 4 30 Freescale Semiconductor System Interface Unit SIU ...
Page 168: ...MSC8113 Reference Manual Rev 0 6 18 Freescale Semiconductor Boot Program ...
Page 180: ...MSC8113 Reference Manual Rev 0 7 12 Freescale Semiconductor Clocks ...
Page 260: ...MSC8113 Reference Manual Rev 0 8 80 Freescale Semiconductor Memory Map ...
Page 300: ...MSC8113 Reference Manual Rev 0 9 40 Freescale Semiconductor Extended Core ...
Page 304: ...MSC8113 Reference Manual Rev 0 10 4 Freescale Semiconductor MQBus and M2 Memory ...
Page 308: ...MSC8113 Reference Manual Rev 0 11 4 Freescale Semiconductor SQBus ...
Page 590: ...MSC8113 Reference Manual Rev 0 17 46 Freescale Semiconductor Interrupt Processing ...
Page 614: ...MSC8113 Reference Manual Rev 0 18 24 Freescale Semiconductor Debugging ...
Page 622: ...MSC8113 Reference Manual Rev 0 19 8 Freescale Semiconductor Internal Peripheral Bus IPBus ...
Page 724: ...MSC8113 Reference Manual Rev 0 21 32 Freescale Semiconductor UART ...
Page 920: ...MSC8113 Reference Manual Rev 0 25 150 Freescale Semiconductor Ethernet Controller ...
Page 1171: ...MSC8113 Reference Manual Rev 0 Freescale Semiconductor C 61 EF wait_rts P 01077FFC 9F rts 71 ...
Page 1172: ...MSC8113 Reference Manual Rev 0 C 62 Freescale Semiconductor MSC8113 Boot Code ...
Page 1202: ...MSC8113 Reference Manual Rev 0 Index 30 Freescale Semiconductor Index ...