Texas Instruments TMS320C2XX User Manual

Page 557

Advertising
background image

F-20

RPTC:

See

repeat counter (RPTC).

RRST:

Receive reset bit. Bit 4 of the synchronous serial port control register

(SSPCR); resets the receiver portion of the synchronous serial port.

RS:

Reset pin. When driven low, causes a reset on any ’C2xx device, includ-

ing the ’C209.

RS:

Reset pin. (On the ’C209 only) When driven high, causes a reset.

RSR:

Receive shift register. Shifts data serially into the synchronous serial

port from the DR pin. See also

XSR.

R/W:

Read/write pin. Indicates the direction of transfer between the ’C2xx

and external program, data, or I/O space.

RX pin:

Asynchronous receive pin. During reception in the asynchronous

serial port, this pin accepts a character one bit at a time, transferring it
to the ARSR.

S

SARAM:

Single-access RAM. RAM that can accessed (read from or written

to) once in a single CPU cycle.

scratch-pad RAM:

Another name for DARAM block B2 in data space (32

words).

SDTR:

Synchronous data transmit and receive register. An I/O-mapped

read/write register that sends data to the transmit FIFO buffer and ex-
tracts data from the receive FIFO buffer.

SETBRK:

Bit 4 of the asynchronous serial port control register (ASPCR);

selects the output level (high or low) on the TX pin when the port is not
transmitting.

short-immediate value:

An 8-, 9-, or 13-bit constant given as an operand

of an instruction that is using immediate addressing.

sign bit:

The MSB of a value when it is seen by the CPU to indicate the sign

(negative or positive) of the value.

sign extend:

Fill the unused high order bits of a register with copies of the

sign bit in that register.

sign-extension mode (SXM) bit:

Bit 10 of status register ST1; enables or

disables sign extension in the input shifter. It also differentiates between
logic and arithmetic shifts of the accumulator.

Glossary

Advertising