NEC UPD98413 User Manual page 88

(b) Receive
The µ PD98413 can switch the receive port from working port to protection port. The method is as follows.
1. Set the same receive port address to the UADR bit of working port and protection port of the PTADRR
register. (In the POS mode, set the same in-band address to the IADR bit of Port0 and Port1 of the
PTADRR register.)
2. Stop the receive FIFO of the protection port by the PnFCLS bit of the MDAPIR register. And enable the
protection port by setting the PnER bit of the PENB register.
3. Disable the working Port by setting the PnER bit of the PENB register.
4. After confirm that the working port FIFO is not busy by the PnBSY bit of the DGE and TGE register, start
the receive FIFO of the protection port by the PnFCLS bit of the MDAPIR register.
(Port3)
Port3
Receive
FIFO
88
CHAPTER 3 FUNCTIONAL OUTLINE
same port address
(setting by the UADR bit of the PTADRR register)
protection
(Port2)
Port2
Receive
FIFO
UTOPIA/POS-PHY
Interface
PRELIMINARY
working port
port
(Port 0)
(Port1)
Port1 Port0
Receive Receive
FIFO FIFO
NEC confidential and Proprietary