80C196NT View Datasheet(PDF) - Intel

Part Name

Description

Manufacturer

80C196NT

CHMOS MICROCONTROLLER WITH 1 MBYTE LINEAR ADDRESS SPACE

Intel 

8XC196NT

PIN DESCRIPTIONS (Continued)

Symbol

Name and Function

P5 2 WR WRL SLPWR

Write and Write Low output to external memory as selected by the CCR WR

will go low for every external write while WRL will go low only for external

writes where an even byte is being written WR WRL is active during external

memory writes Also an LSIO pin when not used as WR WRL SLPWR is the

Slave Port Write Control Input

P5 5 BHE WRH

Byte High Enable or Write High output as selected by the CCR BHEe0

selects the bank of memory that is connected to the high byte of the data bus

A0e0 selects that bank of memory that is connected to the low byte Thus

accesses to a 16-bit wide memory can be to the low byte only (A0e0

BHEe1) to the high byte only (A0e1 BHEe0) or both bytes (A0e0

BHEe0) If the WRH function is selected the pin will go low if the bus cycle is

writing to an odd memory location BHE WRH is only valid during 16-bit

external memory read write cycles Also an LSIO pin when not BHE WRH

P5 6 READY

Ready input to lengthen external memory cycles for interfacing with slow or

dynamic memory or for bus sharing If the pin is high CPU operation continues

in a normal manner If the pin is low prior to the falling edge of CLKOUT the

memory controller goes into a wait state mode until the next positive transition

in CLKOUT occurs with READY high When external memory is not used

READY has no effect The max number of wait states inserted into the bus

cycle is controlled by the CCR CCR1 Also an LSIO pin when READY is not

selected

P5 4 SLPINT

Dual function I O pin As a bidirectional port pin or as a system function The

system function is a Slave Port Interrupt Output Pin

P6 2 T1CLK

Dual function I O pin Primary function is that of a bidirectional I O pin

however it may also be used as a TIMER1 Clock input The TIMER1 will

increment or decrement on both positive and negative edges of this pin

P6 3 T1DIR

Dual function I O pin Primary function is that of a bidirectional I O pin

however it may also be used as a TIMER1 Direction input The TIMER1 will

increment when this pin is high and decrements when this pin is low

PORT1 EPA0–7

P6 0–6 1 EPA8–9

Dual function I O port pins Primary function is that of bidirectional I O System

function is that of High Speed capture and compare EPA0 and EPA2 have yet

another function of T2CLK and T2DIR of the TIMER2 timer counter

PORT 0 ACH4–7

4-bit high impedance input-only port These pins can be used as digital inputs

and or as analog inputs to the on-chip A D converter These pins are also

used as inputs to OTPROM parts to select the Programming Mode

P6 3–6 7 SSIO

Dual function I O ports that have a system function as Synchronous Serial I O

Two pins are clocks and two pins are data providing full duplex capability

PORT 2

8-bit multi-functional port All of its pins are shared with other functions

PORT 3 and 4

8-bit bidirectional I O ports with open drain outputs These pins are shared

with the multiplexed address data bus which has strong internal pullups

EPORT

8-bit bidirectional standard and I O port These bits are shared with the

extended address bus A16 – A19 Pin function is selected on a per pin basis

INTOUT

Interrupt Output This active-low output indicates that a pending interrupt

requires use of the external bus

SLP0 – SLP7

Slave Port Address Data Bus

6

Share Link: