Page x of xxxii
R01UH0025EJ0300 Rev. 3.00
Sep 24, 2010
Section 3 Floating-Point Unit (FPU)................................................................... 67
3.1
Features............................................................................................................................... 67
3.2
Data Formats....................................................................................................................... 67
3.2.1
Floating-Point Format......................................................................................... 67
3.2.2
Non-Numbers (NaN) .......................................................................................... 69
3.2.3
Denormalized Numbers ...................................................................................... 70
3.3
Register Descriptions .......................................................................................................... 71
3.3.1
Floating-Point Registers ..................................................................................... 71
3.3.2
Floating-Point Status/Control Register (FPSCR)................................................ 72
3.3.3
Floating-Point Communication Register (FPUL) ............................................... 73
3.4
Rounding ............................................................................................................................ 74
3.5
FPU Exceptions ..................................................................................................................75
3.5.1
FPU Exception Sources ...................................................................................... 75
3.5.2
FPU Exception Handling .................................................................................... 75
Section 4 Clock Pulse Generator (CPG) ............................................................. 77
4.1
Features............................................................................................................................... 77
4.2
Input/Output Pins................................................................................................................ 80
4.3
Clock Operating Modes ...................................................................................................... 81
4.4
Register Descriptions .......................................................................................................... 87
4.4.1
Frequency Control Register (FRQCR) ............................................................... 87
4.4.2
CKIO Control Register (CKIOCR)..................................................................... 90
4.5
Changing the Frequency ..................................................................................................... 91
4.5.1
Changing the Multiplication Rate ....................................................................... 91
4.5.2
Changing the Division Ratio............................................................................... 92
4.6
Notes on Board Design ....................................................................................................... 93
4.6.1
Note on Inputting External Clock ....................................................................... 93
4.6.2
Note on Using Crystal Resonator ....................................................................... 93
4.6.3
Note on Resonator .............................................................................................. 94
4.6.4
Note on Using a PLL Oscillation Circuit............................................................ 94
4.6.5
Note on Changing the Multiplication Rate ......................................................... 94
Section 5 Exception Handling ............................................................................. 95
5.1
Overview ............................................................................................................................ 95
5.1.1
Types of Exception Handling and Priority ......................................................... 95
5.1.2
Exception Handling Operations .......................................................................... 97
5.1.3
Exception Handling Vector Table....................................................................... 99
5.2
Resets................................................................................................................................ 101
5.2.1
Input/Output Pins.............................................................................................. 101
5.2.2
Types of Reset .................................................................................................. 101