User guide
US
8,549,067
B2
5
bytes
(address,
type
data
checksum)
in
Which
the
data
byte
represents the
status
of
the
IPT-I2C
microcontroller.
The
RBTN
command
sets
the
IPT-I2C
microcontroller
read
type
to
RBTN.
This
means
that
an
I2C
Read
Will
send
four
bytes
(address,
type,
data,
checksum)
in
Which
the
data
byte
represents the
status
of
the
button.
The
RPRB
command
sets
the
IPT-I2C
microcontroller
read
type
to
RPRB.
This
means
that
an
I2C
Read
Will
send
?ve
bytes
(address,
type
data, data,
checksum)
in
Which
the
data
bytes
represent
the
type
of
l-Wire
bus
probe
and
the
probe
data.
The
CRST
command
clears
the
Reset
Flag
(RSTF),
PoWer
On
Reset
Flag
(PORF),
BroWnout
Reset
Flag
(BORF),
and
WatchDog
Reset
Flag
(WDRF)
bits
of
the
IPT-I2C
microcon
troller
status
byte.
The
WDSP
command
sets
the
values
for
the
dual
seven
segment
display.
At
poWer
up,
the
dash-dash
blinks
until
a
valid
WDSP
command
is
received.
After
that,
if
ten
seconds
pass
Without
receiving
a
validWDSP
command,
the
display
reverts
back
to
the
blinking
dash-dash.
A
read
command
is
started
by
the
master
addressing
the
slave
With
the
R/W
bit
set.
A
read
command
to
the
slave
IPT-I2C
microcontroller
results
in
a
?xed
number
of
bytes
repeatedly
being
transmitted
by
the
slave
(address,
type,
datal
dataN
checksum).
The
?rst
byte
is
the
address
of
the
slave.
The
second
byte
indicates
the
type
of
data
in
the
folloWing
data
byte(s).
The
last
byte
is
a
checksum
of
all
the
previous
bytes.
A
Write
command
is
started
by
the
master
addressing
the
slave
With
the
R/W
bit
cleared.
This
is
folloWed
by
the
master
transmitting
multiple
bytes
to
the
slave,
followed
by
a
stop,
or
restart.
The
internal
I2C-bus
119
is
terminated
at
a
netWork
per
sonality
module
(IPT-NetWork
PM)
128,
Such
provides
an
operating
system.
FITTP-server,
and
netWork
interface
betWeen
the
internal
I2C-bus
119,
an
external
I2C-bus
130,
an
Ethernet
10/100
BaseT
132,
a
modem
134,
and
a
local
opera
tor’s
console
136.
The
IPT-NetWorkPM
128
preferably
uses
Internet
protocols
like
TCP/IP
and
supports
simple
netWork
management
protocol
(SNMP).
In
One
applications
the
outlet
strip
100
could
be
used
in
the
remote
poWer
management
environment
described
by
the
present
inventors
in
their
US.
Pat.
No.
5,949,974, issued
Sep.
7,
1999.
Such
patent
is
incor
porated
herein
by
reference.
NetWork
messages,
e.g.,
using
TCP/IP
and
SNMP,
are
communicated
over
the
Ethernet
10/
100
BaseT
interface
132.
Such
messages
are
able
(a)
to
independently
control
the
poWer
on-off
to
each
ofAC-output
receptacles
101-116,
(b)
to
read
the
poWer-on
status
of
each,
and
(c)
to
report
load
current
supplied
by
each
outlet,
or
simply
the
total
combined
current
measured
passing
through
IPT-PS
118.
In
one
embodiment,
the
poWer
applied
to
AC-output
recep
tacles
101-116
is
not
alloWed
by
the
individual
IPT-IPM
modules
120-123
to
be
simultaneously
applied.
Instead,
each
is
alloWed
to
turn
on
in
succession
so
any
instantaneous
load
in-rush
currents
can
not
combine
to
exceed
the
peak
capabili
ties
of
the
AC-poWer
input
source.
The
total
input
current
display
126
could
be
used
to
advan
tage
by
a
technician
When
installing
or
troubleshooting
a
RETMA
equipment
rack
by
Watching
hoW
much
current
change
is
observed
When
each
netWork
appliance
is
plugged
in
and
turned
on.
Unusually
high
or
loW
currents
can
indicate
particular
kinds
of
faults
to
experienced
technicians.
FIGS.
2A
and
2B
represent
a
netWork
remote
poWer
man
agement
outlet
strip
embodiment
of
the
present
invention,
Which
is
referred
to
herein
by
the
general
reference
numeral
20
25
30
35
40
45
50
55
60
65
6
200.
These
illustrate
one
Way
the
netWork
remote
poWer
management
outlet
strip
100
of
FIG.
1
could
be
physically
implemented
and
arranged.
The
outlet
strip
200
provides
independently
managed
poWer
to
each of
sixteen
AC-output
receptacles
201-216.
These
have
AC-neutral
and
AC-ground
bussed
through
tWo
sets
of
eight,
e.
g.,
With
l2-gauge
Wire.
A
poWer
supply
(IPT-PS)
module
218
is
daisy-chained
in
an
internal
I2C-bus
219
to
a
series
of
four
intelligent
poWer
modules
(IPT-IPM)
220-223.
The
IPT-PS
module
218
has,
for
example,
a
Philips
microcontroller
type
87LPC762
that
senses
and
totaliZes
the
combined
current
delivered
on
the
AC-Line
leads
to
all
of
four
intelligent
poWer
modules
(IPT
IPM)
220-223.
The
Philips
87LPC762/7
microcontroller
is
programmed
as
an
I2C
8-bit
I/O
Expander,
With
an
8-bit
4-channel
A/D
converter.
Eight
pins
are
individually
select
able
as
either
an
Input
(quasi-bidirectional)
or
Output
(open
drain).
Four
address
lines
determine
the
I2C
slave
address.
Eight
commands
are
supported:
STAT
(Status),
RCFG
(Read
Con?g)
RPRT
(Read
Port),
RADC
(Read
ADC),
CRST
(Clear
Reset),
WCFG
(Write
Con?g),
WPRT
(Write
Port),
and
ADCE
(ADC
Enable).
A
checksum
is
used
on
received/
sent
bytes
for
data
integrity
across
the
I2C-bus.
Without
a
valid
checksum,
a
command
Will
not
be
acted
upon.
The
microcontroller
starts
up
With
the
I2C
interface
in
idle
slave
mode. Main(
)
Waits
in
a
loop
until
the
I2C
interface
is
?agged
as
non-idle.
After
an
I2C
start’occurs,
and
the
rising
edge
of
SCL
sets
DRDY
and
thus
ATN,
an
I2C
interrupt
occurs.
The
I2C
ISR
disables
the
I2C
interrupt
and
sets
a
global
I2C
non-idle ?ag.
The
main
loop then
proceeds
to
read
in
the
?rst
byte
from
the
I2C-bus.
When
seven
bits
are
received,
the
target
I2C
is
knoWn
and
is
compared
to
the
I/O
Expander’s
oWn
module
address.
If
different,
the
I2C
inter
face
processing
stops
and
Waits
for
another
start
to
begin
again.
If
the
same
the
last
bit
of
the
?rst
byte
is
read,
Which
is
the
R/W
bit.
If
a
Read,
then
the
microcontroller
acknoWledges
the
byte,
and
repeatedly
sends
a
?xed
number
of
response
bytes
(an
address
byte,
a
type byte
one
or
more
data
bytes,
and
a
checksum).
If
a
Write,
then
the
microcontroller
acknoWl
edges
the
byte
and
then
Will
read
up
to
three
more
bytes
(a
command
byte,
a data
byte,
and
a
checksum).
As
received,
the
bytes
are
acknoWledged
and
compared
to
expected
valid
commands
and
data.
As
soon
as
a
valid
command,
any
data
parameters
and
a valid
checksum
are
received
and
acknoWl
edged,
the
command
is
acted
upon.
If
an
unexpected
com
mand
or
data
is
received,
or
more
bytes
are
received
than
expected,
then
a
negative
acknoWledge
occurs
after
the
next
byte
is
received,
and
the
I2C
interface
is
stopped
and
another
start
is
needed
to
begin
again.
Throughout
the
I2C
processing
loop,
a
bus
timeout
by Timer
1
interrupt
resets
the
I2C
inter
face
to
idle
and
the
I2C
processing
loop
to
the
appropriate
state.
Timer
0
also
guards
the
I2C
interface
With
a
5-millisec
ond
inter-clock
timeout
and
a
l5-second
total
I2C
timeout.
The
total
I2C
timeout
is
reset
When
the
I/O
Expander
is
addressed
on
the
I2C
With
its
primary
address,
not
the
sec
ondary
address.
The
I2C
microcontroller
commands
include
the
STAT
command,
Which
sets
the
I/O
Expander
read type
to
STAT.
An
I2C
Read
Will
send
four
bytes:
address,
type,
data,
checksum.
The
data
byte
represents the
status
of
the
I/O
Expander.
The
RCFG
command
sets
the
I/O
Expander
read
type
to
RCFG.
This
means
that
an
I2C
Read
Will
send
four
bytes:
address,
type,
data,
checksum:
The
data
byte
represents
the
I/
O
con?guration
of
the
eight
I/
O
pins.
The
RADC
command
sets
the
microcontroller
read type
to
RADC.
This
means
that
an
I2C
Read
Will
send
eight
bytes
(address,
type,
ADCE
status,
ADCO
data,
ADCI
data,
ADC2
data,
ADC3
data,
checksum)
in
Which
the
data
bytes
represent