NXP Semiconductors
PCF2127
Accurate RTC with integrated quartz crystal for industrial applications
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In this example, the registers Months and Years are read. The pins SDI and SDO are not connected together. For this
configuration, it is important that pin SDI is never left floating. It must always be driven either HIGH or LOW. If pin SDI is left
open, high IDD currents may result.
a. Reading month and year
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b. Reading from RAM address 12h
Fig 39. SPI-bus read examples
DDD
PCF2127
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 8 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
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