參數(shù)資料
型號: intel386 DX
廠商: Intel Corp.
英文描述: 32-Bit CHMOS Microprocessor With Integrated Memory Management(32位CHMOS 微處理器帶集成存儲管理)
中文描述: 32位CHMOS微處理器集成內(nèi)存管理(32位CHMOS微處理器帶集成存儲管理)
文件頁數(shù): 65/139頁
文件大?。?/td> 1587K
代理商: INTEL386 DX
Intel386
TM
DX MICROPROCESSOR
Intel386 DX I/O cycles are automatically generated
for coprocessor communication. Since the Intel386
DX must transfer 32-bit quantities between itself and
the Intel387 DX, BS16
Y
must not be asserted dur-
ing Intel387 DX communication cycles.
5.2.7 Bus Arbitration Signals
(HOLD, HLDA)
5.2.7.1 INTRODUCTION
This section describes the mechanism by which the
processor relinquishes control of its local buses
when requested by another bus master device. See
5.5.1 Entering and Exiting Hold Acknowledge
for
additional information.
5.2.7.2 BUS HOLD REQUEST (HOLD)
This input indicates some device other than the In-
tel386 DX requires bus mastership.
HOLD must remain asserted as long as any other
device is a local bus master. HOLD is not recognized
while RESET is asserted. If RESET is asserted while
HOLD is asserted, RESET has priority and places
the bus into an idle state, rather than the hold ac-
knowledge (high impedance) state.
HOLD is level-sensitive and is a synchronous input.
HOLD signals must always meet setup and hold
times t
23
and t
24
for correct operation.
5.2.7.3 BUS HOLD ACKNOWLEDGE (HLDA)
Assertion of this output indicates the Intel386 DX
has relinquished control of its local bus in response
to HOLD asserted, and is in the bus Hold Acknowl-
edge state.
The Hold Acknowledge state offers near-complete
signal isolation. In the Hold Acknowledge state,
HLDA is the only signal being driven by the Intel386
DX. The other output signals or bidirectional signals
(D0–D31, BE0
Y
–BE3
Y
, A2–A31, W/R
Y
, D/C
Y
,
M/IO
Y
, LOCK
Y
and ADS
Y
) are in a high-imped-
ance state so the requesting bus master may control
them. Pullup resistors may be desired on several sig-
nals to avoid spurious activity when no bus master is
driving them. See
7.2.3 Resistor Recommenda-
tions
. Also, one rising edge occuring on the NMI
input during Hold Acknowledge is remembered, for
processing after the HOLD input is negated.
In addition to the normal usage of Hold Acknowl-
edge with DMA controllers or master peripherals,
the near-complete isolation has particular attractive-
ness during system test when test equipment drives
the system, and in hardware-fault-tolerant applica-
tions.
5.2.8 Coprocessor Interface Signals
(PEREQ, BUSY
Y
, ERROR
Y
)
5.2.8.1 INTRODUCTION
In the following sections are descriptions of signals
dedicated to the numeric coprocessor interface. In
addition to the data bus, address bus, and bus cycle
definition signals, these following signals control
communication between the Intel386 DX and its In-
tel387 DX processor extension.
5.2.8.2 COPROCESSOR REQUEST (PEREQ)
When asserted, this input signal indicates a coproc-
essor request for a data operand to be transferred
to/from memory by the Intel386 DX. In response,
the Intel386 DX transfers information between the
coprocessor and memory. Because the Intel386 DX
has internally stored the coprocessor opcode being
executed, it performs the requested data transfer
with the correct direction and memory address.
PEREQ is level-sensitive and is allowed to be asyn-
chronous to the CLK2 signal.
5.2.8.3 COPROCESSOR BUSY (BUSY
Y
)
When asserted, this input indicates the coprocessor
is still executing an instruction, and is not yet able to
accept another. When the Intel386 DX encounters
any coprocessor instruction which operates on the
numeric stack (e.g. load, pop, or arithmetic opera-
tion), or the WAIT instruction, this input is first auto-
matically sampled until it is seen to be negated. This
sampling of the BUSY
Y
input prevents overrunning
the execution of a previous coprocessor instruction.
The FNINIT and FNCLEX coprocessor instructions
are allowed to execute even if BUSY
Y
is asserted,
since these instructions are used for coprocessor
initialization and exception-clearing.
BUSY
Y
is level-sensitive and is allowed to be asyn-
chronous to the CLK2 signal.
BUSY
Y
serves an additional function. If BUSY
Y
is
sampled LOW at the falling edge of RESET, the In-
tel386 DX performs an internal self-test (see
5.5.3
Bus Activity During and Following Reset
). If
BUSY
Y
is sampled HIGH, no self-test is performed.
65
相關PDF資料
PDF描述
Intel386 EX Highly Integrated, 32-Bit, Fully Static Embedded Micropocessor(32位高集成完全靜態(tài)嵌入式微處理器)
INTEL386 SXSA 5-V 32-Bit Fully Static Embedded Microprocessor(5V,32位完全靜態(tài)嵌入式微處理器)
intel386 SX 32-Bit CPU With a 16-Bit External Data Bus And a 24-bit External Address Bus(帶16位內(nèi)部數(shù)據(jù)總線和24位內(nèi)部地址總線32位微處理器)
INTEL386 Intel386 EX Embedded Microprocessor
Intel387 dx DX Math Coprocessor(32位數(shù)學協(xié)處理器)
相關代理商/技術參數(shù)
參數(shù)描述
INTEL386SX 制造商:INTEL 制造商全稱:Intel Corporation 功能描述:MICROPROCESSOR
INTEL387 制造商:INTEL 制造商全稱:Intel Corporation 功能描述:Intel387TM SX MATH COPROCESSOR
INTEL387DX 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Intel387 DX - MATH COPROCESSOR
INTEL387SX 制造商:INTEL 制造商全稱:Intel Corporation 功能描述:Intel387 SX - MATH COPROCESSOR
INTEL387TMDX 制造商:INTEL 制造商全稱:Intel Corporation 功能描述:Intel387TM DX MATH COPROCESSOR