Intel mcs-48 manual Programmable Interval Timer

inter

8253/8253·5

PROGRAMMABLE INTERVAL TIMER

•	MCS-85™ Compatible 8253·5	•	Count Binary or BCD
•	3 Independent 16·BltCounters	•	Single + 5V Supply
• DC to 2 MHz
•	Programmable Counter Modes	•	24·Pin Dual In·Line Package

The IntelC!> 8253 is a programmable counter/timer chip designed for use as an Intel microcornputer peripheral. It uses nMOS technology with a single +5V supply and is packaged in a 24·pin plastic DiP.

It is organized as 3 independent 16·bitcounters, each with a count rate of up to 2 MHz. All modes of operation are soft· ware programmable.

PIN CONFIGURATION			BLOCK DIAGRAM
0,		Vee			elK 0
o.		ViR
			DATA
		Ali
			BUS		GATE 0
0,	~		BUFFER		our 0
oJ		A,
0,		Ao
0,		eLK 2
Do		OUT 2	RD --~-CI
eLK 0		GATE 2			elK 1
OUT 0		eLK 1			GATE 1
GATE 0		GATE 1
			AO---~
GNO		OUT 1			OUT 1
			Al~-
			CS -------- '
	PIN NAMES				eLK 2
°7,0	DATABUS(8BtTf			COUNTER	GATE 2
elK N	COUNTER CLOCK INPUTS			"2
GATE N	COUNTER GATE INPUTS				OUT 2
OUT N	COUNTER OUTPUTS
RD	READ COUNTER
WR	WRITE COMMAND OR OAT A
CS	CHIP SELECT
A~A	COUNnR SELECT
Vee	+5 VOL T5
GND	GROUND		INTERNAL BUS /

INTEL CORPORATION ASSUMES NO RESPONSIBILITY FOR THE USE OF ANY CIRCUITRY OTHER THAN CIRCUITRY EMBODIED IN AN INTEL PRODUCT. NO OTHER CIRCUIT PATENT LICENSES ARE IMPlIEO.

<lINTEl r.ORPORATION. 1179 9-6 AFN-00145A·01