HD6417320 RENESAS [Renesas Technology Corp], HD6417320 Datasheet - Page 145

• Manufacturer Part Number: HD6417320
• Description: Renesas 32-Bit RISC Microcomputer SuperHTM RISC engine Family / SH7700 Series
• Manufacturer: RENESAS [Renesas Technology Corp]

3.2
3.2.1
The CPU processing modes can be extended using the mode bit (MD) and DSP bit (DSP) in the
status register (SR), as shown below.
Table 3.1
As shown above, the extension of the DSP function by the DSP bit can be specified independently
of the control by the MD bit. Note, however, that the DSP bit can be modified only in privileged
mode. Before the DSP bit is modified, a transition to privileged mode or privileged DSP mode is
necessary.
3.2.2
In DSP mode, a part of the P2 area in the virtual address space can be accessed in user DSP mode.
When this area is accessed in user DSP mode, this area is referred to as a Uxy area. X/Y memory
is then assigned to this Uxy area. Accordingly, X/Y memory can also be accessed in user DSP
mode.
MD
0
0
1
1
DSP
0
1
0
1
DSP Mode Resources
Processing Modes
DSP Mode Memory Map
CPU Processing Modes
Processing Mode
User mode
User DSP mode
Privileged mode
Privileged DSP mode Allowed
Access of Resources
Protected in Privileged Mode
or Privileged Instruction
Execution
Prohibited
Prohibited
Allowed
Rev. 3.00 Jan. 18, 2008 Page 83 of 1458
Description
Section 3 DSP Operating Unit
DSP Extended
Functions
Invalid
Valid
Invalid
Valid
REJ09B0033-0300