Electronic Components Datasheet Search
  English  ▼
ALLDATASHEET.NET

X  

ID82C54 Datasheet(PDF) 6 Page - Intersil Corporation

Part # ID82C54
Description  CMOS Programmable Interval Timer
Download  17 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
Manufacturer  INTERSIL [Intersil Corporation]
Direct Link  http://www.intersil.com/cda/home
Logo INTERSIL - Intersil Corporation

ID82C54 Datasheet(HTML) 6 Page - Intersil Corporation

Back Button ID82C54 Datasheet HTML 2Page - Intersil Corporation ID82C54 Datasheet HTML 3Page - Intersil Corporation ID82C54 Datasheet HTML 4Page - Intersil Corporation ID82C54 Datasheet HTML 5Page - Intersil Corporation ID82C54 Datasheet HTML 6Page - Intersil Corporation ID82C54 Datasheet HTML 7Page - Intersil Corporation ID82C54 Datasheet HTML 8Page - Intersil Corporation ID82C54 Datasheet HTML 9Page - Intersil Corporation ID82C54 Datasheet HTML 10Page - Intersil Corporation Next Button
Zoom Inzoom in Zoom Outzoom out
 6 / 17 page
background image
4-6
A new initial count may be written to a Counter at any time
without affecting the Counter’s programmed Mode in any way.
Counting will be affected as described in the Mode definitions.
The new count must follow the programmed count format.
If a Counter is programmed to read/write two-byte counts,
the following precaution applies. A program must not transfer
control between writing the first and second byte to another
routine which also writes into that same Counter. Otherwise,
the Counter will be loaded with an incorrect count.
Read Operations
It is often desirable to read the value of a Counter without
disturbing the count in progress. This is easily done in the
82C54.
There are three possible methods for reading the Counters.
The first is through the Read-Back command, which is
explained later. The second is a simple read operation of the
Counter, which is selected with the A1, A0 inputs. The only
requirement is that the CLK input of the selected Counter
must be inhibited by using either the GATE input or external
logic. Otherwise, the count may be in process of changing
when it is read, giving an undefined result.
Counter Latch Command
The other method for reading the Counters involves a spe-
cial software command called the “Counter Latch Com-
mand”. Like a Control Word, this command is written to the
Control Word Register, which is selected when A1, A0 = 11.
Also, like a Control Word, the SC0, SC1 bits select one of
the three Counters, but two other bits, D5 and D4, distin-
guish this command from a Control Word.
.
The selected Counter’s output latch (OL) latches the count
when the Counter Latch Command is received. This count is
held in the latch until it is read by the CPU (or until the Counter
is reprogrammed). The count is then unlatched automatically
and the OL returns to “following” the counting element (CE).
This allows reading the contents of the Counters “on the fly”
without affecting counting in progress. Multiple Counter Latch
Commands may be used to latch more than one Counter.
Each latched Counter’s OL holds its count until read. Counter
Latch Commands do not affect the programmed Mode of the
Counter in any way.
If a Counter is latched and then, some time later, latched
again before the count is read, the second Counter Latch
Command is ignored. The count read will be the count at the
time the first Counter Latch Command was issued.
With either method, the count must be read according to the
programmed format; specifically, if the Counter is pro-
grammed for two byte counts, two bytes must be read. The
two bytes do not have to be read one right after the other;
read or write or programming operations of other Counters
may be inserted between them.
Another feature of the 82C54 is that reads and writes of the
same Counter may be interleaved; for example, if the
Counter is programmed for two byte counts, the following
sequence is valid.
LSB of Count - Counter 1
0
1
LSB of Count - Counter 0
0
0
MSB of Count - Counter 0
0
0
MSB of Count - Counter 1
0
1
MSB of Count - Counter 2
1
0
Possible Programming Sequence
A1
A0
Control Word - Counter 2
1
1
Control Word - Counter 1
1
1
Control Word - Counter 0
1
1
LSB of Count - Counter 2
1
0
MSB of Count - Counter 2
1
0
LSB of Count - Counter 1
0
1
MSB of Count - Counter 1
0
1
LSB of Count - Counter 0
0
0
MSB of Count - Counter 0
0
0
Possible Programming Sequence
A1
A0
Control Word - Counter 1
1
1
Control Word - Counter 0
1
1
LSB of Count - Counter 1
0
1
Control Word - Counter 2
1
1
LSB of Count - Counter 0
0
0
MSB of Count - Counter 1
0
1
LSB of Count - Counter 2
1
0
MSB of Count - Counter 0
0
0
MSB of Count - Counter 2
1
0
NOTE: In all four examples, all counters are programmed to
Read/Write two-byte counts. These are only four of many
programming sequences.
Possible Programming Sequence (Continued)
A1
A0
A1, A0 = 11; CS = 0; RD = 1; WR = 0
D7
D6
D5
D4
D3
D2
D1
D0
SC1
SC0
0
0
XXXX
SC1, SC0 - specify counter to be latched
SC1
SC0
COUNTER
00
0
01
1
10
2
1
1
Read-Back Command
D5, D4 - 00 designates Counter Latch Command, X - Don’t Care.
NOTE: Don’t Care bits (X) should be 0 to insure compatibility with
future products.
82C54


Similar Part No. - ID82C54

ManufacturerPart #DatasheetDescription
logo
Intersil Corporation
ID82C54 INTERSIL-ID82C54 Datasheet
386Kb / 22P
   CMOS Programmable Intervel Timer
More results

Similar Description - ID82C54

ManufacturerPart #DatasheetDescription
logo
UMC Corporation
UM82C54 UMC-UM82C54 Datasheet
1Mb / 16P
   CMOS PROGRAMMABLE INTERVAL TIMER
logo
Intersil Corporation
CS82C54-10Z96 INTERSIL-CS82C54-10Z96 Datasheet
426Kb / 22P
   CMOS Programmable Interval Timer
logo
Renesas Technology Corp
82C54 RENESAS-82C54 Datasheet
679Kb / 23P
   CMOS Programmable Interval Timer
Sep 15, 2015
logo
OKI electronic componet...
MSM82C53-2RS OKI-MSM82C53-2RS Datasheet
149Kb / 19P
   CMOS PROGRAMMABLE INTERVAL TIMER
MSM82C54-2RS OKI-MSM82C54-2RS Datasheet
161Kb / 23P
   CMOS PROGRAMMABLE INTERVAL TIMER
logo
Mitsubishi Electric Sem...
M5M82C54P MITSUBISHI-M5M82C54P Datasheet
916Kb / 11P
   CMOS PROGRAMMABLE INTERVAL TIMER
logo
Toshiba Semiconductor
TMP82C53 TOSHIBA-TMP82C53 Datasheet
326Kb / 15P
   PROGRAMMABLE INTERVAL TIMER
logo
Intel Corporation
8254 INTEL-8254 Datasheet
835Kb / 21P
   PROGRAMMABLE INTERVAL TIMER
logo
Samsung semiconductor
KS82C54 SAMSUNG-KS82C54 Datasheet
953Kb / 15P
   PROGRAMMABLE INTERVAL TIMER
logo
Digital Core Design
D8254 DCD-D8254 Datasheet
132Kb / 4P
   Programmable Interval Timer
More results


Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17


Datasheet Download

Go To PDF Page


Link URL




Privacy Policy
ALLDATASHEET.NET
Does ALLDATASHEET help your business so far?  [ DONATE ] 

About Alldatasheet   |   Advertisement   |   Contact us   |   Privacy Policy   |   Link Exchange   |   Manufacturer List
All Rights Reserved©Alldatasheet.com


Mirror Sites
English : Alldatasheet.com  |   English : Alldatasheet.net  |   Chinese : Alldatasheetcn.com  |   German : Alldatasheetde.com  |   Japanese : Alldatasheet.jp
Russian : Alldatasheetru.com  |   Korean : Alldatasheet.co.kr  |   Spanish : Alldatasheet.es  |   French : Alldatasheet.fr  |   Italian : Alldatasheetit.com
Portuguese : Alldatasheetpt.com  |   Polish : Alldatasheet.pl  |   Vietnamese : Alldatasheet.vn
Indian : Alldatasheet.in  |   Mexican : Alldatasheet.com.mx  |   British : Alldatasheet.co.uk  |   New Zealand : Alldatasheet.co.nz
Family Site : ic2ic.com  |   icmetro.com