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DSP56853/854/855/857/858 User’s Manual
MOTOROLA
Preliminary
Register Descriptions (ESSI0_BASE = $1FFE20, ESSI1_BASE = $1FFE00)
12
12.7.7.5 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 the timing of the last slot. When the TLIE bit in the SCR3 register is disabled
the status bit will 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
12.7.7.6 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 a 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
12.7.7.7 Transmit FIFO 1 Error (TF1ERR)—Bit 9
When the transmitter status control TXSF1 is set and FIFOs are in use, this status bit will
indicate the state of FIFO 1 is not the same as FIFO 0. If transmitter 0 (TXSF0 = 0) is not
in use this flag can never be set.
0 = State of TXFIFO0 and TXFIFO1 are the same (contain the same amount of
data)
1 = State of TXFIFO0 is different than the state of TXFIFO1
12.7.7.8 Transmit FIFO 2 Error (TF2ERR)—Bit 8
When the transmitter status control TXSF2 is set and FIFOs are in use, this status bit
indicates the state of FIFO2 is not the same as FIFO0. If transmitter 0 (TXSF0 = 0) is not
in use, this status bit will indicate the state of FIFO2 is not the same as FIFO1. If
transmitter 1 is also not operating (TXSF0 = TXSF1 = 0), this flag can never be set.