MT8986 Mitel Semiconductor, MT8986 Datasheet - Page 14

• Manufacturer Part Number: MT8986
• Description: CMOS ST-BUS FAMILY Multiple Rate Digital Switch
• Manufacturer: Mitel Semiconductor

MT8986
* - only in the 44 pin packages.
** - for Data Memory Read operations A0 is not required since two nibbles are provided per read access.
Note: In rate conversion applications, Data Memory subsections have different sizes than Connection Memory subsections. This
2-76
Nibble Switch
Different
2 Mb/s to
2 Mb/s to
4 Mb/s to
8 Mb/s to
4 Mb/s
8 Mb/s
2 Mb/s
2 Mb/s
Identical
Rate
2 Mb/s *
2 Mb/s *
(2 Mb/s)
I/O
2 Mb/s
4 Mb/s
4 Mb/s
8 Mb/s
implies that different address inputs are used to select individual positions within the subsections for each type of memory.
Rate
I/O
Streams
Config.
Input x
Output
8x4
8x2
4x8
2x8
# of Input x
Streams
Output
16x8 *
4x4 *
Table 7. Use of STA Bits for Different I/O Data Rate Operation
Table 6. Use of STA Bits for Identical I/O Data Rate Operation
8x8
4x4
8x4
2x2
8x4
STA2, STA1,
STA0
STA2, STA1,
STA0
STA1, STA0
STA0
STA bits used
subsections
to select
Memory
Data
STA2, STA1, STA0
STA1, STA0
STA3, STA2, STA1,
STA0
STA1, STA0
STA2, STA1, STA0
STA0
STA2, STA1, STA0
select subsections
STA bits used to
of the Data
Memory
STA1, STA0
STA0
STA2, STA1,
STA0
STA2, STA1,
STA0
STA bits used
subsections
Connection
to select
Memory
STA2, STA1, STA0
STA1, STA0
STA2, STA1, STA0
STA1, STA0
STA1, STA0
STA0
STA1, STA0
subsections of the
STA bits used to
Input Address pins used
A4, A3, A2, A1, A0
A4, A3, A2, A1, A0
A6, A4, A3, A2, A1, A0
A7, A6, A4, A3, A2, A1,
A0
Connection
selected subsection
to access individual
positions within the
Memory
select
Data Memory
A4, A3, A2, A1, A0
A4, A3, A2, A1, A0
A4, A3, A2, A1, A0
A6, A4, A3, A2, A1, A0
A6, A4, A3, A2, A1, A0
A7, A6, A4, A3, A2, A1, A0
A6, A4, A3, A2, A1, A0 **
Memory positions within the
Input Address pins used to
Connection and Data
selected subsection
Input Address pins used
A6, A4, A3, A2, A1, A0
A7, A6, A4, A3, A2, A1,
A0
A4, A3, A2, A1, A0
A4, A3, A2, A1, A0
select individual
Connection Memory
to access individual
selected subsection
positions within the