EM77F900 Datasheet, PDF (72/136 Pages) ELAN Microelectronics Corp – USB HUB+BB Controller

EM77F900
USB HUB+BB Controller
Bit 7: LOW_MODE
Enables or disables low power mode for RFW-102:
0: Disables low mode (normal mode)
1: Enables low mode. BB is in RX mode, while RFW-102 is in TX mode.
User has to put the BB into RX mode and disable RX and PREAMBLE
search, before enabling LOW_MODE. This transfers the RFW-102 to TX
mode using RX_TX pin, while the BB is still in RX mode.
RFW-102 power consumption is lower in TX mode than in RX mode. BB
cannot remain in TX mode, if it is not transmitting. Low mode is the
combination of both of the above.
Default Value: 0x01
8.3.8 System Control Register 4 (SCR4)
This register is a read and a write register.
Name Bit 7 Bit 6 Bit 5 Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
SCR4 N/A N/A N/A N/A FIFO FLAGS WIN CONT RF_ACTIVE IE
Bit 0: IE
This flag enables all interrupts when set to ‘1’.
When ‘0’ all interrupts are disabled.
Bit 1: RF_ACTIVE
This bit controls the RF_ACTIVE pin. When this bit is high the RF Modem is
active.
Bit 2: WIN CONT
This bit determines the size of the WINDOW in the Preamble search
module.
IF (BLR+6)>14 and WIN_CONT=1, then the preamble window size is 5
Bit 3: FIFO FLAGS
Determines the RX_FIFO AF flag and TX_FIFO AE flag:
IF FIFO FLAGS = 0 then AF = 12 and AE = 4
IF FIFO FLAGS = 1 then AF = 8 and AE = 8
Default Value: 0x00.
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Product Specification (V1.0) 07.31.2007
(This specification is subject to change without further notice)