User`s manual

Software Manual • EKF Intelligent I/O Controller Family On CompactPCI
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EKF Elektronik GmbH * Philipp-Reis-Str. 4 * D-59065 HAMM (Germany)
Tel. [phone] * Fax. [phone] * E-Mail [e-mail] * Internet http://www.ekf.de
Board Level Interface Description
This chapter describes the low level interface to a board of the EKF Intelligent I/O Controller
family. It is dedicated to those software developers that have to write a driver for such a
board.
To support driver writers, EKF delivers C header files that contain most of the necessary
stuff like structure and macro definitions.
Board Firmware
EKF's Intelligent I/O Controllers are based on Intel's i960
®
Rx processor, a powerful 32-bit
I/O controller which incorporates a multi-function PCI interface. The PCI device consists of
a PCI-to-PCI Bridge at PCI function 0 and an Address Translation Unit (ATU) at PCI
function 1. The Messaging Unit (called MU) is a part of the ATU. The MU is the core of the
I/O board's interface.
The on-board firmware boots up automatically after power up or board reset (factory setting
of the configuration jumper field JCNF on the I/O boards). It first initializes the local devices
like memory, I/O ports and the (Compact)PCI interface, i.e. the MU. During this time all
configuration cycles from the PCI interface to the board will be retried.
After all local initializations are done, PCI configuration cycles will be accepted again. At this
time the hosts BIOS is able to scan for the device and to initialize its PCI resources. Thus it
can be assumed that the controller is ready to work as soon as PCI cycles to it are possible.
Messa
g
in
g
Unit
The messaging unit provides data transfers between the PCI system and the i960
®
RP. It
uses interrupts to notify each system when new data arrives. The MU has four messaging
mechanisms: Message Registers, Doorbell Registers, Circular Queues and Index Registers.
Each allows a host processor or external PCI device and the i960
®
RP to communicate
through message passing and interrupt generation.
The MU is part of the primary Address Translation Unit (ATU) that is shortly described in the
following section.