C8051F124-GQR Datasheet, PDF (143/350 Pages) Silicon Laboratories – Mixed Signal ISP Flash MCU Family

C8051F120/1/2/3/4/5/6/7
C8051F130/1/2/3
SFR Definition 11.4. SFRNEXT: SFR Next Register
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W Reset Value
00000000
Bit7
Bit6
Bit5
Bit4
Bit3
Bit2
Bit1
Bit0
SFR Address: 0x85
SFR Page: All Pages
Bits7–0:
SFR Page Stack Bits: SFR page context is retained upon interrupts/return from interrupts in
a 3 byte SFR Page Stack: SFRPAGE is the first entry, SFRNEXT is the second, and SFR-
LAST is the third entry. The SFR stack bytes may be used alter the context in the SFR Page
Stack, and will not cause the stack to ‘push’ or ‘pop’. Only interrupts and return from inter-
rupts cause pushes and pops of the SFR Page Stack.
Write: Sets the SFR Page contained in the second byte of the SFR Stack. This will cause
the SFRPAGE SFR to have this SFR page value upon a return from interrupt.
Read: Returns the value of the SFR page contained in the second byte of the SFR stack.
This is the value that will go to the SFR Page register upon a return from interrupt.
SFR Definition 11.5. SFRLAST: SFR Last Register
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Reset Value
00000000
Bit7
Bit6
Bit5
Bit4
Bit3
Bit2
Bit1
Bit0
SFR Address: 0x86
SFR Page: All Pages
Bits7–0:
SFR Page Stack Bits: SFR page context is retained upon interrupts/return from interrupts in
a 3 byte SFR Page Stack: SFRPAGE is the first entry, SFRNEXT is the second, and SFR-
LAST is the third entry. The SFR stack bytes may be used alter the context in the SFR Page
Stack, and will not cause the stack to ‘push’ or ‘pop’. Only interrupts and return from inter-
rupts cause pushes and pops of the SFR Page Stack.
Write: Sets the SFR Page in the last entry of the SFR Stack. This will cause the SFRNEXT
SFR to have this SFR page value upon a return from interrupt.
Read: Returns the value of the SFR page contained in the last entry of the SFR stack.
Rev. 1.4
143