Xycom XVME-240 Manual page 30

XVME-240 Manual
October, 1984
Any location within the DIO's 1K I/O Interface Block can be accessed by adding the
module base address to the address of the specific location within the I/O Interface
Block (referred to as the I/O Interface Block offset). For example, the module
Status/Control register is located at address 81H within the I/O Interface Block. If
the module base address is set to a value of 1000H then the Status/Control register
would be accessed at address 1081H.
(Module Base
Address)
l000H
For memory-mapped CPU modules (such as 68000 CPU modules), the Short I/O
Address Space is memory-mapped to begin at a specific address. For such modules the
I/O Interface Block offset is an offset from the start of this memory-mapped Short I/O
Address space. For example, if the Short I/O space of a 68000 CPU module starts at
F9OOOOH and if the base address of the DIO is jumpered to 1000H, the actual module
base address would be F9l000H.
3.3 THE DIO I/O INTERFACE BLOCK
The 1K block of Short I/O Address space allotted to the DIO (see Figure 3-1) is divided
into specific areas which are dedicated to performing the following functions:
Module identification data for the
-
Module status and control
-
Data I/O ports and registers for controlling
-
3.3.1 Module
Identification Data (Base+0lH
The XYCOM module identification scheme provides a unique method of registering
module-specific information in an ASCII encoded format. The I.D. data is provided as
thirty-two ASCII encoded characters consisting of the board type, manufacturer
identification, module model number, number of 1K byte blocks occupied by the
module, and module functional revision level information.
read by the system processor on power-up to verify the system configuration and
operational status. Table 3-1 defines the Identification information locations.
(I/O Interface
Block Offset)
+ 0 8 1 H
(Status/Control
Register)
=
1 0 8 1 H
DIO
and interrupts
I/O
to 3FH - odd byte locations only)
3-3
This information can be