max2986cxv Maxim Integrated Products, Inc., max2986cxv Datasheet - Page 17

• Manufacturer Part Number: max2986cxv
• Description: Integrated Powerline Digital Transceiver Integrated Products
• Manufacturer: Maxim Integrated Products, Inc.

Figure 18 shows the transmit timing. t
that data must be valid for after a low-to-high transition
on ETHTXCLK. t
after a low-to-high transition on ETHTXCLK. Figure 19
shows the receive timing. t
the positive edge of ETHRXCLK. t
after the positive edge of ETHRXCLK. For further infor-
mation on the Ethernet MAC interface, refer to the IEEE
802.3 specification.
Figure 20 shows the structure of a USB cable. The two
pins USBD+ and USBD- are the data pins used in the
USB interface, and correspond to D+ and D- in Figure
20. V
Figure 18. Transmit Timing for Ethernet MAC Interface to the
MAX2986
Figure 19. Receive Timing for Ethernet MAC Interface to the
MAX2986
Figure 20. USB Cable
V
ETHRXD[3:0],
ETHTXD[3:0]
GND
BUS
ETHTXCLK
D+
D-
ETHRXCLK
ETHTXEN
ETHTXER
ETHRXDV
BUS
is nominally +5V at the source. Figure 10
TXDH
Integrated Powerline Digital Transceiver
______________________________________________________________________________________
is the time that data must be held
t
t
RXS
t
TXDV
TXDV
t
RXS
> 10ns
< 25ns
RXS
t
RXH
is the setup time prior to
t
TXDH
RXH
t
TXDH
t
RXH
USB Interface
> 5ns
< 10ns
TXDV
is the hold time
is the time
V
D-
GND
D+
BUS
shows the upper layer interface pin setting to select
USB. Refer to the Universal Serial Bus Specification,
Revision 1.1 for more details on the USB interface.
A serial asynchronous communication protocol using
the UART standard interface is implemented in the
MAX2986 baseband chip for the purpose of down-
load/debugging MAC software. To communicate with
the current MAC software, the UART interface must be
configured as shown in Table 11.
To download and debug HomePlug MAC software, a null
modem cable is required to make a serial connection as
shown in Figure 21. The MAX3221 is used as UART driver.
Figure 21. MAX2986 UART Interface with Driver and DB9
Connector
Table 10. Upper Layer Interface-Selection
Pin Settings
Table 11. UART Interface Configuration
Data Rate
Data Length
Stop Bit
Flow Control
INTERFACE
USB
MAX2986
BASEBAND
UARTRXD
UARTTXD
GPIO[3]
0
MAX3221
DRIVER
UART
115,200bps
8 Bits
1 Bit
None
OUT
GPIO[6]
IN
0
UART Interface
DB9 CONNECTOR
8
GPIO[4]
1
6
2
7
3
4
9
5
0
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