Molex SST-PB3-VME-1 and SST-PB3-VME-2 Hardware Reference Guide

Molex SST-PB3-VME-1 and SST-PB3-VME-2 Hardware Reference Guide 

Purpose of this Guide

This guide contains technical and product-related information on the SST-PB3-VME-1   and SST-PB3-VME-2 network interface cards.  

The SST-PB3-VME-1 consists of a single Profibus network interface (or channel), and the   SST-PB3-VME-2 comprises two independent interfaces, controlled by independent CPUs.   Each CPU executes downloadable application firmware modules, which enable application-level product behavior. For more details, refer to relevant firmware documentation.

Note An application running on one channel does not affect the performance of other channels, as it does not share memory or processor resources with them.

Note In this manual, the SST-PB3-VME-1 and SST-PB3-VME-2 will be referred to as the card, except where product differences apply.

Conventions

This guide uses stylistic conventions, special terms, and special notation to help enhance your understanding.

Style

The following stylistic conventions are used throughout this guide:

Terminology

The following special terms are used throughout this guide:

Special Notation

The following special notations are used throughout this guide:

Warnng

Warning messages alert the reader to situations where personal injury may result. Warnings are accompanied by the symbol shown, and precede the topic to which they refer.

Caution

Caution messages alert the reader to situations where equipment damage may result. Cautions are accompanied by the symbol shown, and precede the topic to which they refer.

Note

A note provides additional information, emphasizes a point, or gives a tip for easier operation. Notes are accompanied by the symbol shown, and follow the text to which they refer.

Hardware Description

The main features of the card are described in more detail in the following sections.

Figure 1:   The SST-PB3-VME-1 and SST-PB3-VME-2 Interface Card

LEDs

The LEDs are illustrated in the following diagram and described below.  

Figure 2:   Assembled Mounting Bracket –Front View

SYSFail LED

The SysFail LED indicates the system’s status.

Watchdog LED

The Watchdog LED indicates that a watchdog timeout has occurred on the channel.

Table 3:    Watchdog LED Behavior

Sys LED

The Sys LED indicates the status of each channel on the card.

Comm LED

The COMM LED indicates the communications status of each channel on the card.

Selecting the Proper Line Type

Use this table to determine which line type best suits system requirements.

Profibus Connector

The card has one standard Profibus DB9 female connector per channel. Pin numbers are identified in the following figure.

The recommended cable is Belden 3079A. Examples include:

• Brad Harrison 85-0001 PVR 2 conductor with shield, UL-listed Profibus cable 

 • Bosch Comnet DP #913 548 Flexible Profibus Cable 

 • Bosch Comnet DP #917 201 Trailing Profibus Cable 

 • Bosch Comnet DP #917 202 Massive Profibus Cable  

DIP Switch (S1)

The card has a 10-position DIP switch that must be set before the card is installed.   The DIP switch is used to set the base I/O address used to configure the card.

Setting the Short I/O Base Address

The 1 Kbyte block of short address space occupied by the card is located on a 1 Kbyte boundary at an address selected by positions 1 through 6 of the switch. These switch positions correspond to address bits A15 through A10, respectively. Therefore, when all switches are ON, the base address for Channel A is 0x0000, with the channel responding to short space addresses 0001, 0003, 0005, 0007, and 0009; and the base address for Channel B is 0x200, with the channel responding to short space addresses 0x0201, 0x203, 0x205 and so on.

Access Privileges

The card provides 8-bit access to objects in the short address space and 8- and 16-bit access to objects in the standard address space. The VME master selects whether a particular bus cycle accesses short, standard, extended, or long (extended and long are not used on the card) address spaces, and the type of access, through the use of the address modifier codes. The card decodes these address modifier codes and determines the object to be accessed. In addition to selecting one of four spaces available on the VMEbus, address modifier codes also select: 

 • Whether the master is making a supervisory or non-privileged access   

• Whether the access is to program or data space (for all but short address space accesses) 

 • Whether it is to be a single-object or block access The card can respond to address modifier codes 0x03D, 0x039, 0x02D, and 0x029.   Supervisory or non-privileged data accesses may be made to standard address space (0x03D and 0x039 respectively). Supervisory or non-privileged accesses may be made to short address space (0x02D and 0x029 respectively). An access to the card with an address modifier code that is not supported causes a VMEbus error. Position 7 of the card's DIP switch selects whether only supervisory accesses or both supervisory and non-privileged accesses are permitted. The following table shows the switch positions.

Interrupts

The card can generate and acknowledge interrupts on any one of VMEbus interrupt lines 1 through 7 (or none). The interrupt level is selected by positions 8 through 10 of switch S1, as detailed below:

The card interrupter is a ROAK (release-on-acknowledge) type. The interrupt request is removed from the VMEbus when the card responds to an interrupt acknowledge. However, the Card-IRQ bit in the Control register remains set until cleared by the host.

Default Switch Settings

The card is shipped with all switches ON. This corresponds to: 

 • Short I/O address 0000 

 • Supervisory and non-privileged access permitted 

 • Interrupts disabled