HPC167064 datasheet(13/34 Pages) NSC

13 / 34 page

Connection Diagram

TLDD11046 – 17

Top View

Order Number HPC167064 EL

See NS Package Number EL68C

PortsAB

The highly flexible A and B ports are similarly structured

The Port A (see

Figure 11 ) consists of a data register and a

direction register Port B (see

Figures 12 thru Figure 14 ) has

an alternate function register in addition to the data and

direction registers All the control registers are readwrite

registers

The associated direction registers allow the port pins to be

individually programmed as inputs or outputs Port pins se-

lected as inputs are placed in a TRI-STATE mode by reset-

ting corresponding bits in the direction register

A write operation to a port pin configured as an input causes

the value to be written into the data register a read opera-

tion returns the value of the pin Writing to port pins config-

ured as outputs causes the pins to have the same value

reading the pins returns the value of the data register

Primary and secondary functions are multiplexed onto Port

B through the alternate function register (BFUN) The sec-

ondary functions are enabled by setting the corresponding

bits in the BFUN register

TLDD11046 – 19

FIGURE 11 Port A IO Structure

HPC167064 Datasheet(PDF) 13 Page - National Semiconductor (TI)