PIN DEFINITIONS, (CON’T)

Copyright ©1998-2001 Semtech Corporation

DOC8-007-0A4 -DS-104

www.semtech.com

6

Pin Numbers

Mnemonic

QFP

Type

Name and Function

Host Communication

Interface

_SS/_RTS

13

I_Int

Slave_Select (SPI Mode) or

Ready_To_Send (Asynchronous Serial

Mode). Active-Low signal Input. Low-level

indicates that the Host System has data

for the UR8HC007 peripheral device or the

Host System is ready to accept data from

the UR8HC007 peripheral device.

Capable of Interrupt on Negative edge.

Pin 60 and pin 18 should both be "Low" for

data exchange to occur.

_ATN/_CTS

18

O

Attention (SPI Mode) or Clear_To_Send

(Asynchronous Serial Mode ). Active-Low

signal Output. Low-level indicates that the

UR8HC007 peripheral device has data for

the Host System or the UR8HC007

peripheral device is ready to accept data

from the Host System. Pin 18 and pin 60

should both be "Low" for data exchange to

occur.

MISO/TXD

20

I/O / O

Master-In-Slave-Out (SPI Mode) or

Transmit Data (Asynchronous Serial Mode,

Idle = "High" = 1)

MOSI/RXD

21

I

Master-Out-Slave-In (SPI Mode) or Receive

Data (Asynchronous Serial Mode)

SCLK/_ISEL

19

I

Serial Clock (SPI Mode) or Interface Select

(Asynchronous Serial Mode). Tie "Low" to

select Asynchronous Serial Mode. In SPI

Mode, use the following Clock sequence:

Idle-High / Negative-Edge (Shift Data) \

Positive-Edge (Latch Data), Idle-High.

PS/2 Port

PS2CLK

6

15V/

PS/2 Clock line

nD5V

PS2DATA

7

15V/

PS/2 Data line

nD5V

Note 2: An underscore before a pin mnemonic denotes an active low signal.

Pin Types Legend: PWR= Power; Ai=Analog Input; Ao= Analog Output; I=Digital Input;

I_Int=Digital Input capable of generating interrupts on a positive to negative edge transition;

I±Int=Digital Input capable of generating interrupts on either a positive or a negative edge

transition of the input signal; Ipup= Digital Input with built-in Pull-up to VDD; O=Output; pD=

p-channel open Drain Output (switch to VDD); I/O=Input or Output (Bidirectional pin); nD= n-

channel open Drain Output (switch to VSS); 15V= 5 Volt tolerant input (even if VDD is less

than 5V); nD5V=5 Volt tolerant n-channel open Drain Output.