AN2244 Freescale Semiconductor / Motorola, AN2244 Datasheet - Page 5

• Manufacturer Part Number: AN2244
• Description: Interconnecting Two MSC8101ADS Boards Across a 60x-Compatible Bus to the Host Interface
• Manufacturer: Freescale Semiconductor / Motorola

2.3 Physical Interconnections
Pin No.
C14
C15
C16
C17
C18
C19
C20
C21
C22
C23
C24
C25
C26
C27
C28
C29
A10
A11
A14
A15
P1
C4
Pin No.
P2
Host MSC8101 Side
The most important aspect of the HDI16 host interface for our purposes is that it is specified as an
asynchronous interface, reducing concerns over clock skew between the HDI16 host interface and the
host device buses. Furthermore, since the host MSC8101 accesses all the HDI16 registers in the HDI16
MSC8101 with a single chip select and four address lines, the DSP host interface is in effect an
asynchronous memory-mapped region. For the HDI16 host interface in single-strobe mode, the host
device asserts a chip select, a single data strobe, and a read/write line to select HDI16 read or write bus
operations. The read and write strobes are also used as the data latch control to complete the bus
transactions, avoiding the need for any handshake termination signal from the DSP.
Through appropriate mode selection, the HDI16 feature set is fully supported by the host MSC8101
UPM-controlled signals. The UPM-defined interface can be used with any of the host MSC8101’s eight
chip selects to give the 16-bit port size and strobe generation matching that of the HDI16 MSC8101
device’s host interface.
Table 1 shows the physical interconnections between the host MSC8101ADS UPM-controlled system
bus and the host interface port of the HDI16 MSC8101ADS. The connectors specified in this table refer
to the corresponding connector names, as defined in the MSC8101 Application Development System
User’s Manual.
Signal Name
BTOLCS1
System + CPM Edge Connector
EXPD10
EXPD11
EXPD12
EXPD13
EXPD14
EXPD15
EXPA25
EXPA26
EXPA29
EXPA30
EXPD0
EXPD1
EXPD2
EXPD3
EXPD4
EXPD5
EXPD6
EXPD7
EXPD8
EXPD9
Freescale Semiconductor, Inc.
Table 1. Physical MSC8101ADS Interconnects
1
For More Information On This Product,
60x-Compatible Data Bus
Signal Description
Go to: www.freescale.com
Chip Select 6
Address Bus
P4 = H0
Pin No.
10
11
12
13
14
15
16
17
18
21
22
23
24
25
26
3
4
5
6
7
8
9
Signal Name
HCS1
HCS2
HD10
HD11
HD12
HD13
HD14
HD15
System Bus–HDI16 Host Interface
HD0
HD1
HD2
HD3
HD4
HD5
HD6
HD7
HD8
HD9
HA0
HA1
HA2
HA3
HDI16 MSC8101 Side
HDI16 Connector
Host Interface Address Lines
Host Bidirectional Data Port
Tie this to 3.3V (P4, Pin 33)
Signal Description
Host Chip Select 1
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