pca9673 NXP Semiconductors, pca9673 Datasheet - Page 8

• Manufacturer Part Number: pca9673
• Description: Remote 16-bit I/o Expander For Fm+ I2c-bus With Interrupt And Reset
• Manufacturer: NXP Semiconductors

NXP Semiconductors
PCA9673_1
Product data sheet
7.2.1 Software Reset
7.2.2 Device ID (PCA9673 ID field)
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 PCA9673 does not initiate a reset of its registers.
The unique sequence that initiates a Software Reset is described in
The Device ID field is a 3-byte read-only (24 bits) word giving the following information:
1. A START command is sent by the I
2. The reserved General Call I
3. The PCA9673 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 12. 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 PCA9673 acknowledges this value only. If the byte is not equal to 06h, the
If more than 1 byte of data is sent, the PCA9673 does not acknowledge any more.
STOP command to end the Software Reset sequence: the PCA9673 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.
8 bits with the manufacturer name, unique per manufacturer (for example,
NXP Semiconductors).
13 bits with the part identification, assigned by manufacturer, the 7 MSBs with the
category ID and the 6 LSBs with the feature ID (for example, PCA9673 16-bit
quasi-output I/O expander).
2
C-bus master must interpret a non-acknowledge from the PCA9673 (at any time) as
PCA9673 does not acknowledge it.
2
C-bus master.
2
Remote 16-bit I/O expander for Fm+ I
S
START condition
C-bus is functional and that there is no device hanging the bus.
SWRST Call I
2
C-bus master.
0
Rev. 01 — 1 February 2007
0
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
PCA9673 is(are) reset.
C-bus with interrupt and reset
0
1
acknowledge
from slave(s)
1
0
002aac307
Figure
A
PCA9673
© NXP B.V. 2007. All rights reserved.
P
12.
8 of 33