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Register Descriptions (ESSI0_BASE = $1FFE20, ESSI1_BASE = $1FFE00)
5685X Digital Signal Controller User Manual, Rev. 4
12-32
Freescale Semiconductor
Shift Register is transferred into the Receive Data Register. If it is not enabled, the IF0 bit is
cleared.
12.8.7.3 Reserved—Bit 13
This bit is reserved or not implemented. It cannot be read nor modified by writing.
12.8.7.4 Transmit FIFO Full (TFF)—Bit 12
This status bit allows monitoring when the Transmit FIFO is full. The state of this bit reflects the
status of the transmitter(s) selected by the TXSF0-2 control bits.
0 = Transmit FIFO can accept more data
1 = Transmit FIFO is full
12.8.7.5 Transmit Last Slot (TLS)—Bit 11
This is a status bit indicating the timing of the last transmit slot during the Network mode
operation. When this bit is set, the Transmit Last Slot Interrupt is asserted. The interrupt service
routine for this interrupt should read the Status Register, then write 1 to this bit to clear the
interrupt.
If the Transmit Last Slot Interrupt is not enabled, this bit can be read by the software to determine
only be asserted during the last slot timing.
0 = Not currently transmitting the last time slot of the transmit frame
1 = Last slot of the transmit frame is currently being transmitted
12.8.7.6 Receive Last Slot (RLS)—Bit 10
This is a status bit indicating the timing of the last receive slot during the Network mode
operation. When this bit is set, the Receive Last Slot (RLS) interrupt bit is asserted. The interrupt
service routine for this interrupt should read the Status Register and then write 1 to this bit to
clear the interrupt.
If the RLS interrupt is not enabled, this bit can be read by the software to determine the timing of
the last slot. When the RLIE bit in the SCR3 register is disabled the status bit will only be
asserted during the last slot timing.
0 = Not currently receiving the last time slot of the receive frame
1 = Last slot of the receive frame is currently being received