Siemens ERTEC200 Manual De Usuario

 

 
The ERTEC 200 can also be operated from an external host processor. The LBU bus interfaces are available for this 
purpose: 
 
The bus system is selected using the CONFIG[2] input pin. 
 
CONFIG[2] = 0 

LBU bus system is active 

CONFIG[2] = 1 

LBU bus system is inactive (supplemental function PHY debug, ETM trace, GPIO[44:32] can be 

activated) 
 
The LBU is a 16-bit data interface.  
 
The following signal pins are available for the LBU on the ERTEC 200. 
 

• 

Data bus  

 

16 bit 

LBU_D[15 : 0] 

• 

Address bus  

 

21 bit 

LBU_A[20 : 0] 

• Memory 

CS 

 

1 

LBU_CS_M_N 

• Register 

CS 

 

1 

LBU_CS_R_N 

• RD/WR 

config   

1 

LBU_CFG 

• 

RD/WR 

  2 

LBU_WR_N / LBU_RD_N 

• 

Ready 

  2 

LBU_POL_RDY, LBU_RDY_N 

• Byte 

selection   

2 

LBU_BE[1 : 0] 

• 

Page segment selection 

2 

LBU_SEG[1 : 0] 

• Interrupt 

outputs 

 

2 

LBU_IRQ0_N, LBU_IRQ1_N 

 
Four different pages within the ERTEC 200 can be accessed via the LBU.  
Each page can be set individually. 
 
The settings for the four pages are made via the LBU page registers. Five page registers are available per page. These 
registers are used for the size, offset, and access width settings of the page. The "LBU_CS_R_N" chip select signal can 
be used  to access the page registers. 
 
The following settings are possible for each page: 

• 

Access size of a page between 256 bytes and 2 Mbytes with 2-page range register 

• 

Offset (segment) of page in 4-Gbyte address area with 2-page offset register 

• 

Access type (data bit width) with 1 page control register 

 
After the page register has been configured, the ERTEC 200 internal address area is accessed via the LBU_CS_M_N 
chip select signal.   
The LBU supports accesses to the address area with separate read and write cables or with a common read/write cable.  
 
The access type is set using the Config[5] configuration input.  
 

0 

Separate RD/WR cable 

1 

LBU_WR_N has RD/WR control 

 
The polarity of the ready signal is set via the Config[6] configuration input. 
 

0 Low 

active 

1 High 

active 

 
LBU_RDY_N is a tristate output and must be pulled to his “ready” level by an external pull-down or pull-up resistor. 
During an access from the LBU-Interface to the ERTEC 200  (CS with RD or WR activ) , the LBU_RDY_N switched to 
inactiv (Wait) first. LBU_RDY_N will be active for a 50 MHz-Clock if data will be read or write. After that LBU_RDY_N 
switched back to tristate. The external Pull- (up/down) resistor drives the ready state. 

 

Copyright © Siemens AG 2007. All rights reserved.                  

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Technical data subject to change                                                                                                                                Version 1.1.0