Beckhoff EtherCAT Technology Section I Bedienungsanleitung PDF herunterladen (Seite 100)

SII EEPROM

I-80 Slave Controller – Technology

11.3.3.2 Read Access

An EEPROM read access reads 2 or 4 words (4 or 8 bytes, depending on device capabilities) from the

EEPROM, the load or reload EEPROM access typically reads 8 words (16 bytes). The address wrap-

around at the end of the EEPROM address space has to be taken into account by the application; the

ESC has no knowledge about it.

The ESC will perform the following steps for a read access to the EERPOM. At first, the address is

written to the EEPROM, then the data is read (N=3 or N=7):

Table 45: I²C Read Access

Step

Description

Up to 16 Kbit

32 Kbit – 4 Mbit

Start condition

Control Byte (Write)

A[10:8]

A[18:16]

High Address Byte

Not present

A[15:8]

Low Address Byte

A[7:0]

Start condition

Control Byte (Read)

A[10:8]

A[18:16]

Data Byte 0

D0 [7:0]

Data Byte 1

D1 [7:0]

…

N+7

Data Byte N

DN [7:0]

N+8

Stop condition

* This step is only for EEPROMs larger than 16 Kbit.

11.3.4 Timing specifications

Table 46: EEPROM timing characteristics

Parameter

Comment

Clk

EEPROM clock period

Write

Write access time (without errors)

Read

Read access time (without errors)

Delay

Time until configuration loading begins after

Reset is gone

R/W1 001

EEPROM_CLK

A10

EEPROM_DATA

Clk

A8A9 Ack A7 A5A6 A4 A2A3 A1 Ack

Start Control Byte Low Address Byte

D3 D1D2 Ack D15 D13D14 D12 D10D11 D9 D8

Data Byte 0 Data Byte 1

D0D7 D5D6 D4

EEPROM_CLK

EEPROM_DATA

Stop

Ack

Write

Figure 38: Write access (1 address byte, up to 16 Kbit EEPROMs)

1 2 ... 95 96 97 98 99 100 101 102 103 104 105 ... 115 116

Kommentare zu diesen Handbüchern

Keine Kommentare

Beckhoff EtherCAT Technology Section I Bedienungsanleitung Seite 100

Kommentare zu diesen Handbüchern

Verwandte Produkte und Handbücher für Ausrüstung Beckhoff EtherCAT Technology Section I