MK50H27PLCC datasheet(15/56 Pages) STMICROELECTRONICS

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CSR

DATA

4.1.1.2 Register Data Port (RDP)

BIT

NAME

DESCRIPTION

15:00

CSR DATA

Writing data to the RDP loads data into the CSR selected by RAP. Reading the data from

RDP reads the data from the CSR selected in RAP.

4.1.2 Control and Status Register Definition

4.1.2.1 Control and Status Register 0 (CSR0)

RAP<3:1> = 0

BIT

NAME

DESCRIPTION

TDMD

TRANSMIT DEMAND, when set, causes MK50H27 to access the

Transmit Descriptor Ring without waiting for the transmit polltime inter-

val to elapse. TDMD need not be set to transmit a MSU, it merely has-

tens MK50H27’s response to a Transmit Descriptor Ring entry inser-

tion by the host. TDMD is Write With ONE ONLY and cleared by the

microcode after it is used. It may read as a ”1” for a short time after it

is written because the microcode may have been busy when TDMD

was set. It is also cleared by Bus RESET. Writing a ”0” in this bit has

no effect.

POFF

POFF, when set, indicates that MK50H27 is operating in the Power Off

phase of operation. All external activity is disabled and internal logic is

reset. MK50H27 remains inactive except for primitive processing until

a Power On primitive is issued. POFF IS READ ONLY and set by Bus

RESET or a Power Off primitive. Writing to this bit has no effect.

DTX

Transmitter ring disable prevents the MK50H27 from further access to

the Transmitter Descriptor Ring and terminates transmitter polling. No

transmissions are attempted after finishing transmission of any signal

unit in transmission at the time of DTX being set. TXON acknow-

ledges changes to DTX, see below. DTX is READ/WRITE.

MK50H27

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MK50H27PLCC Datasheet(PDF) 15 Page - STMicroelectronics