參數(shù)資料
型號: CD1865
廠商: Intel Corp.
英文描述: Intelligent Eight-Channel Communications Controller
中文描述: 智能八通道通信控制器
文件頁數(shù): 56/150頁
文件大?。?/td> 871K
代理商: CD1865
CD1865
Intelligent Eight-Channel Communications Controller
56
Datasheet
To recognize how this difference can cause a problem, suppose that the three Service Request lines
from the CD1865 are connected to levels 7, 6, and 5 of the VME bus (see
Figure 19 on page 56
).
Also, attach a 74XX244 so that during an Interrupt Acknowledgment cycle provides an 8-bit code
consisting of the three address bits plus five more hard-wired bits to the CD1865. Now, whenever
an acknowledgment of a level 5, 6, or 7 interrupt occurs, the CD1865 either responds or passes the
acknowledgment properly. If an acknowledgment occurs on levels 1
4, the daisy chain
breaks
because the CD1865 does not recognize a match.
This condition can be easily rectified, as shown in
Figure 20 on page 57
. A PAL is used to assert
ACKOUT* whenever ACKIN* occurs on a level not being used by the CD1865. The PAL is
programmed for fixed levels. For example, if the current VME bus Interrupt level is 1
4, the PAL
asserts ACKOUT* whenever ACKIN* is active. If the current level is 5
7, the PAL asserts
ACKOUT* when ACKOUT* from the CD1865 is active. If required, the assignment of VME
Interrupt levels to the CD1865 can be field-programmable by supplying additional inputs to the
PAL, indicating the levels being used by the CD1865.
Figure 19. Incorrect VME Interface
CD1865
A0
A6
RREQ*
TREQ*
MREQ*
ACKOUT* ACKIN*
74XX244
ARBITRARY
VALUE
A1
A3
IRQ7*
IRQ6*
IRQ5*
ACKIN*
ACKOUT*
A1
A7
VME BUS
(BUFFERS NOT SHOWN)
IACK*
相關(guān)PDF資料
PDF描述
CD22100 CMOS 4 x 4 Crosspoint Switch with Control Memory High-Voltage Type (20V Rating)
CD22100E CMOS 4 x 4 Crosspoint Switch with Control Memory High-Voltage Type (20V Rating)
CD22100F CMOS 4 x 4 Crosspoint Switch with Control Memory High-Voltage Type (20V Rating)
CD22101 CMOS 4 x 4 x 2 Crosspoint Switch with Control Memory
CD22101E CMOS 4 x 4 x 2 Crosspoint Switch with Control Memory
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
CD1865N 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Analog IC
CD1865P 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Analog IC
CD1866N 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Analog IC
CD1866P 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Analog IC
CD1867N 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Analog IC