Renesas R5S72623 Benutzerhandbuch
Page xii of xl
R01UH0134EJ0400 Rev. 4.00
Sep
24,
2014
Section 3 Floating-Point Unit (FPU) ................................................................... 95
3.1
Features ............................................................................................................................... 95
3.2
Data Formats ....................................................................................................................... 96
3.2.1
Floating-Point Format ......................................................................................... 96
3.2.2
Non-Numbers (NaN) .......................................................................................... 99
3.2.3
Denormalized Numbers .................................................................................... 100
3.3
Register Descriptions ........................................................................................................ 101
3.3.1
Floating-Point Registers ................................................................................... 101
3.3.2
Floating-Point Status/Control Register (FPSCR) ............................................. 102
3.3.3
Floating-Point Communication Register (FPUL) ............................................. 104
3.4
Rounding .......................................................................................................................... 105
3.5
FPU Exceptions ................................................................................................................ 106
3.5.1
FPU Exception Sources .................................................................................... 106
3.5.2
FPU Exception Handling .................................................................................. 106
Section 4 Boot Mode ......................................................................................... 109
4.1
Features ............................................................................................................................. 109
4.2
Boot Mode and Pin Function Setting ................................................................................ 109
4.3
Operation .......................................................................................................................... 110
4.3.1
Boot Mode 0 ..................................................................................................... 110
4.3.2
Boot Modes 1 and 3 .......................................................................................... 110
4.3.3
Boot Mode 2 ..................................................................................................... 111
4.4
Notes ................................................................................................................................. 114
4.4.1
Boot Related Pins ............................................................................................. 114
Section 5 Clock Pulse Generator ....................................................................... 115
5.1
Features ............................................................................................................................. 115
5.2
Input/Output Pins .............................................................................................................. 118
5.3
Clock Operating Modes .................................................................................................... 119
5.4
Register Descriptions ........................................................................................................ 122
5.4.1
Frequency Control Register (FRQCR) ............................................................. 122
5.5
Changing the Frequency ................................................................................................... 125
5.5.1
Changing the Division Ratio ............................................................................. 125
5.6
Usage of the Clock Pins .................................................................................................... 126
5.6.1
In the Case of Inputting an External Clock ....................................................... 126
5.6.2
In the Case of Using a Crystal Resonator ......................................................... 127
5.6.3
In the Case of Not Using the Clock Pin ............................................................ 127
5.7
Oscillation Stabilizing Time ............................................................................................. 128
5.7.1
Oscillation Stabilizing Time of the On-chip Crystal Oscillator ........................ 128