zl50411 Zarlink Semiconductor, zl50411 Datasheet - Page 22

• Manufacturer Part Number: zl50411
• Description: Managed 9-port Fast Ethernet Switch With Private Vlan
• Manufacturer: Zarlink Semiconductor

1.5
TSTOUT[15:0] and M[7:0]_TXEN pins serve as bootstrap pins during device power-up or reset. Please refer to
“Typical Reset & Bootstrap Timing Diagram” on page 130 for more information on when the bootstrap pins are
sampled. The bootstrap pins require external pull-up/down resistors for proper operation. Recommend 10 K for
pull-ups and 1 K for pull-downs.
The table below summarizes the bootstrap options.
1.5.1
The following are the recommended default settings for the bootstrap options:
•
CPU Interface
Ethernet Interface
Misc. Features
Unmanaged/Lightly Managed
•
•
Bootstrap Options
Reserved/Manufacturing bootstraps
-
-
CPU Interface:
-
-
Recommended Default Bootstrap Settings
TSTOUT[15:13,8] must be pulled-up
TSTOUT[10] must be pulled-down
Strobe debounce bootstrap, TSTOUT[0], should be normally pulled-up, unless you wish to disable the
debounce logic
CPU Interface bootstrap, TSTOUT[3:1], should be pulled-up to indicate unmanaged SSI CPU
interface. To enable SSI-only lightly managed mode, pulled-down TSTOUT[3]. To enable SSI+MII
lightly managed mode, pulled-down TSTOUT[3,1]
Feature
8/16-bit parallel, serial with MII, serial only and unmanaged serial with I
EEPROM.
TSTOUT[3:1] is used to select the interface options mentioned above. If the
serial interface is selected, addition bootstrap options are required:
•
•
Also, in unmanaged mode, an optional I
the device at power-up or reset. TSTOUT[7] selects the EEPROM option.
The ZL50411 supports module hotswap on all it's ports. This is enabled via
TSTOUT[9]. When enabled, bootstrap pins M[7:0]_TXEN (ports 0-7) are used
to specify the module type to support multiple ethernet interfaces during
module hotswap.
Another feature is the MAC power savings mode. When enabled via
TSTOUT[11], each port's MAC will detect inactivity on the port and go into a
power savings state. When activity is detected once again on the port, the MAC
will come out of this state.
One other feature selected via bootstrap is Timeout Reset Enable
(TSTOUT[12]). This enables a monitoring block with the device which will
detect if any hardware state machine is in a non-idle state for more than 5
seconds.
Refer to section 2.7 for more details on this feature.
The ZL50411 allows the selection of 5 different management interfaces:
TSTOUT[0] enables or disables the DEBOUNCE feature (refer to
“Synchronous Serial Interface” on page 35)
TSTOUT[6:4] selects the device ID
Table 4 - Bootstrap Features
Zarlink Semiconductor Inc.
ZL50411
22
Description
2
C EEPROM can be used to configure
Data Sheet
2
C