C8051F566-IQR Silicon Labs, C8051F566-IQR Datasheet - Page 98

• Manufacturer Part Number: C8051F566-IQR
• Description: 8-bit Microcontrollers - MCU 50 MIPS 16 kB 2 kB LIN 2.1 SPI
• Manufacturer: Silicon Labs

Specifications of C8051F566-IQR

• Rohs: yes
• Core: 8051
• Processor Series: C8051
• Data Bus Width: 8 bit

C8051F55x/56x/57x
While CIP-51 executes in-line code (writing values to SPI0DAT in this example), the CAN0 Interrupt
occurs. The CIP-51 vectors to the CAN0 ISR and pushes the current SFR Page value (SFR Page 0x00)
into SFRNEXT in the SFR Page Stack. The SFR page needed to access CAN’s SFRs is then automatically
placed in the SFRPAGE register (SFR Page 0x0C). SFRPAGE is considered the “top” of the SFR Page
Stack. Software can now access the CAN0 SFRs. Software may switch to any SFR Page by writing a new
value to the SFRPAGE register at any time during the CAN0 ISR to access SFRs that are not on SFR
Page 0x0C. See Figure 12.3.
SFR Page 0xC
Automatically
pushed on stack in
SFRPAGE on CAN0
interrupt
0xC
SFRPAGE
(CAN0)
SFRPAGE
pushed to
0x0
SFRNEXT
SFRNEXT
(SPI0DAT)
SFRLAST
Figure 12.3. SFR Page Stack After CAN0 Interrupt Occurs
98
Rev. 1.1