User`s manual

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Appendix A I/O File Format
High-performance Embedded Workshop formats the [IO] window based on information it finds in an I/O
Register definition file. When you select a debugging platform, High-performance Embedded Workshop will
look for a “<device>.IO” file corresponding to the selected device and load it if it exists. This file is a formatted
text file that describes the I/O modules and the address and size of their registers. You can edit this file, with a
text editor, to add support for memory mapped registers or peripherals you may have specific to your application
(e.g. registers in an ASIC device mapped into the microcomputer's address space).
The following describes two formats of the “<device>.IO” file that supports or not the bit field.
A.1 File format (Bit Field Not Supported)
Each module name must be defined in the [Modules] definition section and the numbering of each module must
be sequential. Each module corresponds to a register definition section and within the section each entry defines
an I/O register.
The [BaseAddress] definition is for devices where the location of I/O registers moves in the address space
depending on the CPU mode. In this case, the [BaseAddress] value is the base address of the I/O registers in one
specific mode and the addresses used in the register definitions are the address locations of the registers in the
same mode. When the I/O register file is actually used, the [BaseAddress] value is subtracted from the defined
register address and the resultant offset added to the relevant base address for the selected mode.
The [Register] definition entry is entered in the format <name> = <address> [<size> [<absolute>]].
1. <name> register name to be displayed.
2. <address> address of the register.
3. <size> which may be B, W or L for byte, word, or longword (default is byte).
4. <absolute> which can be set to A if the register is at an absolute address. This is only relevant
if the I/O area address range moves about on the CPU in different modes. In this case, if a
register is defined as absolute the base address offset calculation is not performed and the
specified address is used directly.
Comment lines are allowed and must start with a “;” character.
An example is shown below.