CS5463 datasheet(39/44 Pages) CIRRUS

39 / 44 page

CS5463

DS678PP1

8. AUTO-BOOT MODE USING E2PROM

When the CS5463 MODE pin is asserted (logic 1), the

CS5463 auto-boot mode is enabled. In auto-boot mode,

the CS5463 downloads the required commands and

the CS5463 to begin performing energy measurements.

8.1 Auto-boot Configuration

A typical auto-boot serial connection between the

CS5463 and a E2PROM is illustrated in Figure 17. In au-

to-boot mode, the CS5463’s CS and SCLK are config-

ured as outputs. The CS5463 asserts CS (logic 0),

provides a clock on SCLK, and sends a read command

to the E2PROM on SDO. The CS5463 reads the us-

er-specified commands and register data presented on

the SDI pin. The E2PROM’s programmed data is utilized

by the CS5463 to change the designated registers’ de-

fault values and begin registering energy.

Figure 17 also shows the external connections that

would be made to a calibrator device, such as a PC or

custom calibration board. When the metering system is

installed, the calibrator would be used to control calibra-

tion and/or to program user-specified commands and

calibration values into the E2PROM. The user-specified

commands/data will determine the CS5463’s exact op-

eration, when the auto-boot initialization sequence is

running. Any of the valid commands can be used.

8.2 Auto-boot Data for E2PROM

Below is an example code set for an auto-boot se-

quence. This code is written into the E2PROM by the us-

er. The serial data for such a sequence is shown below

in single-byte hexidecimal notation:

64 00 00 60

Write Operation Mode Register, turn high-pass

filters on.

44 7F C4 A9

Write value of 0x7FC4A9 to Current Gain

48 FF B2 53

Write value of 0xFFB253 to Voltage Gain

74 00 00 04

Unmask bit #2 (LSD) in the Mask Register.

Start continuous conversions

78 00 01 00

Write STOP bit to Control Register, to terminate

auto-boot initialization sequence.

8.3 Which E2PROMs Can Be Used?

Several industry-standard serial E2PROMs that will suc-

cessfully run auto-boot with the CS5461A are listed be-

low:

•

Atmel AT25010, AT25020 or AT25040

•

National Semiconductor NM25C040M8 or NM25020M8

•

Xicor X25040SI

These types of serial E2PROMs expect a specific 8-bit

command (00000011) in order to perform a memory

read. The CS5461A has been hardware programmed to

transmit this 8-bit command to the E2PROM at the be-

ginning of the auto-boot sequence.

CS5463

EEPROM

EOUT1

EOUT2

MODE

SCLK

SDI

SDO

SCK

Connector to Calibrator

VD+

5 K

Mech. Counter

Stepper Motor

Figure 17. Typical Interface of E2PROM to CS5463

CS5463 数据表(PDF) 39 Page - Cirrus Logic

CS5463 数据表(HTML) 39 Page - Cirrus Logic

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44

数据表下载