SH7205 Datasheet, PDF (129/1904 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperHTM RISC engine Family / SH7200 Series

Section 3 Floating-Point Unit (FPU)
3.3 Register Descriptions
3.3.1 Floating-Point Registers
Figure 3.4 shows the floating-point register configuration. There are sixteen 32-bit floating-point
registers FPR0 to FPR15, referenced by specifying FR0 to FR15, DR0/2/4/6/8/10/12/14. The
correspondence between FRPn and the reference name is determined by the PR and SZ bits in
FPSCR. Refer figure 3.4.
1. Floating-point registers, FPRi (16 registers)
FPR0 to FPR15
2. Single-precision floating-point registers, FRi (16 registers)
FR0 to FR15 indicate FPR0 to FPR15
3. Double-precision floating-point registers or single-precision floating-point vector registers in
pairs, DRi (8 registers)
A DR register comprises two FR registers.
DR0 = {FR0, FR1}, DR2 = {FR2, FR3}, DR4 = {FR4, FR5}, DR6 = {FR6, FR7},
DR8 = {FR8, FR9}, DR10 = {FR10, FR11}, DR12 = {FR12, FR13}, DR14 = {FR14, FR15}
Reference name
Transfer instruction case:
Operation instruction case:
FPSCR.SZ = 0
FPSCR.PR = 0
FR0
FR1
FR2
FR3
FR4
FR5
FR6
FR7
FR8
FR9
FR10
FR11
FR12
FR13
FR14
FR15
FPSCR.SZ = 1
FPSCR.PR = 1
DR0
DR2
DR4
DR6
DR8
DR10
DR12
DR14
Register name
FPR0
FPR1
FPR2
FPR3
FPR4
FPR5
FPR6
FPR7
FPR8
FPR9
FPR10
FPR11
FPR12
FPR13
FPR14
FPR15
Figure 3.4 Floating-Point Registers
Rev. 1.00 Mar. 25, 2008 Page 97 of 1868
REJ09B0372-0100