[etherlab-dev] Read of slave EtherCAT EEPROM from PDI not possible with the Etherlab EtherCAT Master

Frank K. Larsen fkl at deif.com
Tue Jan 15 15:40:06 CET 2013

Hello etherlab-dev

I have experienced that the Etherlab EtherCat Master does not release the Slave EEPROM for PDI access like TwinCAT do?

I use Beckhoff ET1100 ASIC's for my slaves.

Using the command line tool I can manipulate the Slave register to allow the PDI to read the EEPROM so that my slaves can update the SDO object 0x1018 subindex 4 from EEPROM.

>From a ASCII terminal:
~ # ethercat -p2 reg_read 0x500 -t uint16  <-- Read EEPROM config register
0x0000 0
~ # ethercat -p2 reg_write 0x500 1 -t uint16 <-- Set bit 0 in config register
~ # ethercat -p2 reg_read 0x500 -t uint16
0x0001 1                                     <-- Now the bit is set, the slave PDI can access the EEPROM

My slaves updates the object (0x1018) on a transition from INIT to PREOP

~ # ethercat sl
0  0:0  PREOP  +  PCM5.1 Power and Control Module
1  0:1  PREOP  +  PDM5.2 Power and Distributed Communication Module
2  0:2  PREOP  +  IOM5.1 Input and Output Module
~ # ethercat -p2 st init
~ # ethercat -p2 st preop
~ # ethercat -p2 reg_read 0x500 -t uint16  <-- Bit is not altered by the master
0x0001 1
~ # ethercat -p2 upload 0x1018 4 -t uint32  <-- Read object 0x1018 subindex 4 - serial number
0x01020304 16909060                         <-- My slave serial number

I propose that the master by default allows the slaves to read the EEPROM from PDI side by setting this bit (register 0x500.0 = 1) when it is not used by the master.

Med venlig hilsen/Best regards/Viele GrĂ¼ssen

Frank Kjul Larsen
DEIF Wind Power Technology
SW Developer B.Sc.E.E.

Tel.:    +45 9614 8462

fkl at deif.com


Frisenborgvej 33
DK-7800 Skive

Tel.: +45 9614 9614 
Fax:  +45 9614 9615


DEIF Power and Marine you find at www.deif.com

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