Philips Semiconductors

Product specification

SCC2691

Universal asynchronous receiver/transmitter (UART)

1998 Sep 04

16

RDN

MPI

WRN

MPO

SD00125

Figure 5. I/O Timing

WRN

INTERRUPT1

OUTPUT

RDN

INTERRUPT1

OUTPUT

NOTES:

1. INTRN or MPO when used as interrupt outputs.

2. The test for open drain outputs is intended to guarantee switching of the output transistor. Measurement of this response is referenced from the midpoint of the switching signal,

are pronounced and can greatly affect the resultant measurement.

SD00126

Figure 6. Interrupt Timing

X1/CLK

C/T CLK

RxC

TxC

C1

C2

Y1

X1/CLK

X2

SCC2691

C1 = C2 = 24pF

CLK

5V

470

Ω

X1

X2

N/C

TYPICAL CRYSTAL SPECIFICATION

FREQUENCY. . . . . . . . . . . . . . 2–4MHz

TYPE OF OPERATION . . . . . .PARALLEL RESONANT, FUND. MODE

DRIVING

FROM EXTERNAL

SOURCE

50k

to

150k

SD00127

Figure 7. Clock Timing