Four Modes of Operation:

− Hold (Store)

− Shift Right

− Shift Left

− Load Data

Operates With Outputs Enabled or at High

Impedance

3-State Outputs Drive Bus Lines Directly

Can Be Cascaded for N-Bit Word Lengths

Direct Overriding Clear

Applications:

− Stacked or Pushdown Registers

− Buffer Storage

− Accumulator Registers

description/ordering information

These 8-bit universal shift/storage registers

feature multiplexed I/O ports to achieve full 8-bit

data handling in a single 20-pin package. Two

function-select (S0, S1) inputs and two

output-enable (OE1, OE2) inputs can be used to

choose the modes of operation listed in the

function table.

Synchronous parallel loading is accomplished by

taking both S0 and S1 high. This places the

3-state outputs in a high-impedance state and

permits data that is applied on the I/O ports to

be clocked into the register. Reading out of the register can be accomplished while the outputs are enabled in

any mode. Clearing occurs when the clear (CLR) input is low. Taking either OE1 or OE2 high disables the outputs

but has no effect on clearing, shifting, or storage of data.