87C196KS Intel Corporation, 87C196KS Datasheet - Page 5

• Manufacturer Part Number: 87C196KS
• Description: ADVANCED 16-BIT CHMOS MICROCONTROLLER
• Manufacturer: Intel Corporation

PIN DESCRIPTIONS
P5 5 BHE WRH
P5 6 READY
P5 4 SLPINT
P6 2 T1CLK
P6 3 T1DIR
PORT1 EPA0 – 7
P6 0–6 1 EPA8– 9
PORT 0 ACH0 – 7
P6 3–6 7 SSIO
PORT 2
PORT 3 and 4
Symbol
Byte High Enable or Write High output as selected by the CCR BHE
bank of memory that is connected to the high byte of the data bus A0
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 (A0
(A0
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 write cycles Also an LSIO pin when not
BHE WRH
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
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
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
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
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
8-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
EPROM parts to select the Programming Mode
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
8-bit multi-functional port All of its pins are shared with other functions
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
(Continued)
e
1 BHE
e
0) or both bytes (A0
Name and Function
e
0 BHE
e
e
0) If the WRH function is selected
0 BHE
e
1) to the high byte only
87C196KT 87C196KS
e
e
0 selects the
0 selects
5
5