PCF2123U/5GA/1 View Datasheet(PDF) - NXP Semiconductors.
Part Name
Description
MFG CO.
'PCF2123U/5GA/1' PDF : 63 Pages View PDF
NXP Semiconductors
PCF2123
SPI Real time clock/calendar
Table 43. Command byte definition
Bit
Symbol
Value
7
R/W
0
1
6 to 4 SA
001
3 to 0 RA
0h to Fh
Description
data read or data write selection
write data
read data
subaddress; other codes will cause the device
to ignore data transfer
register address range
In Figure 25, the register Seconds is set to 45 seconds and the register Minutes is set to
10 minutes.
R/W
addr 02HEX
seconds data 45BCD
minutes data 10BCD
b7 b6 b5 b4 b3 b2 b1 b0 b7 b6 b5 b4 b3 b2 b1 b0 b7 b6 b5 b4 b3 b2 b1 b0
000100100100010100010000
SCL
SDI
CE
address
counter
xx
02
Fig 25. Serial bus write example
03
04
001aaf915
R/W
addr 07HEX
months data 11BCD
years data 06BCD
b7 b6 b5 b4 b3 b2 b1 b0 b7 b6 b5 b4 b3 b2 b1 b0 b7 b6 b5 b4 b3 b2 b1 b0
100101110001000100000110
SCL
SDI
SDO
CE
address
counter
xx
07
Fig 26. Serial bus read example
08
09
001aaf916
PCF2123
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 6 — 15 July 2013
© NXP B.V. 2013. All rights reserved.
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