pca9672 NXP Semiconductors, pca9672 Datasheet - Page 7

• Manufacturer Part Number: pca9672
• Description: Pca9672 Remote 8-bit I/o Expander For Fm I?c-bus With Interrupt And Reset
• Manufacturer: NXP Semiconductors

NXP Semiconductors
PCA9672_2
Product data sheet
7.2.1 Software Reset
The Software Reset Call allows all the devices in the I
state value through a specific formatted I
implies that the I
The Software Reset sequence is defined as following:
The I
a ‘Software Reset Abort’. The PCA9672 does not initiate a reset of its registers.
The unique sequence that initiates a Software Reset is described in
1. A START command is sent by the I
2. The reserved General Call I
3. The PCA9672 device(s) acknowledge(s) after seeing the General Call address
4. Once the General Call address has been sent and acknowledged, the master sends
5. Once the right byte has been sent and correctly acknowledged, the master sends a
Fig 9. Software Reset sequence
is sent by the I
‘0000 0000’ (00h) only. If the R/W bit is set to 1 (read), no acknowledge is returned to
the I
1 byte. The value of the byte must be equal to 06h.
a. The PCA9672 acknowledges this value only. If the byte is not equal to 06h, the
If more than 1 byte of data is sent, the PCA9672 does not acknowledge any more.
STOP command to end the Software Reset sequence: the PCA9672 then resets to
the default value (power-up value) and is ready to be addressed again within the
specified bus free time. If the master sends a Repeated START instead, no reset is
performed.
2
C-bus master must interpret a non-acknowledge from the PCA9672 (at any time) as
PCA9672 does not acknowledge it.
2
C-bus master.
2
S
START condition
C-bus is functional and that there is no device hanging the bus.
Remote 8-bit I/O expander for Fm+ I
SWRST Call I
2
C-bus master.
0
0
Rev. 02 — 6 July 2007
0
2
0
C-bus address
0
2
C-bus address ‘0000 000’ with the R/W bit set to 0 (write)
0
acknowledge
from slave(s)
0
2
R/W
C-bus master.
0
2
Registers are set to default power-up values.
C-bus command. To be performed correctly, it
A
0
0
SWRST data = 06h
0
2
0
C-bus to be reset to the power-up
2
PCA9672 is(are) reset.
C-bus with interrupt and reset
0
1
acknowledge
from slave(s)
1
0
002aac329
Figure
A
PCA9672
© NXP B.V. 2007. All rights reserved.
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