C8051F575-IM Silicon Laboratories Inc, C8051F575-IM Datasheet - Page 99

• Manufacturer Part Number: C8051F575-IM
• Description: IC 8051 MCU 16K FLASH 40-QFN
• Manufacturer: Silicon Laboratories Inc
• Series: C8051F57xr

Specifications of C8051F575-IM

• Program Memory Type: FLASH
• Program Memory Size: 16KB (16K x 8)
• Package / Case: 40-QFN
• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 50MHz
• Connectivity: EBI/EMI, SMBus (2-Wire/I²C), SPI, UART/USART
• Peripherals: POR, PWM, Temp Sensor, WDT
• Number Of I /o: 33
• Ram Size: 2.25K x 8
• Voltage - Supply (vcc/vdd): 1.8 V ~ 5.25 V
• Data Converters: A/D 32x12b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 125°C
• Processor Series: C8051F5x
• Core: 8051
• Data Bus Width: 8 bit
• Data Ram Size: 2304 B
• Maximum Clock Frequency: 50 MHz
• Number Of Programmable I/os: 33
• Operating Supply Voltage: 1.8 V to 5.25 V
• Maximum Operating Temperature: + 125 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: PK51, CA51, A51, ULINK2
• Development Tools By Supplier: C8051F560DK
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: 336-1691 - KIT DEVELOPMENT FOR C8051F560
• Eeprom Size: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 336-1716-5

While in the CAN0 ISR, a PCA interrupt occurs. Recall the PCA interrupt is configured as a high priority
interrupt, while the CAN0 interrupt is configured as a low priority interrupt. Thus, the CIP-51 will now vector
to the high priority PCA ISR. Upon doing so, the CIP-51 will automatically place the SFR page needed to
access the PCA’s special function registers into the SFRPAGE register, SFR Page 0x00. The value that
was in the SFRPAGE register before the PCA interrupt (SFR Page 0x0C for CAN0) is pushed down the
stack into SFRNEXT. Likewise, the value that was in the SFRNEXT register before the PCA interrupt (in
this case SFR Page 0x00 for SPI0DAT) is pushed down to the SFRLAST register, the “bottom” of the
stack. Note that a value stored in SFRLAST (via a previous software write to the SFRLAST register) will be
overwritten. See Figure 12.4.
Figure 12.4. SFR Page Stack Upon PCA Interrupt Occurring During a CAN0 ISR
SFRPAGE
SFRNEXT
SFRNEXT
pushed to
SFRLAST
pushed to
(SPI0DAT)
SFRPAGE on PCA
pushed on stack in
(CAN0)
SFR Page 0x0
Automatically
(PCA)
0xC
0x0
0x0
interrupt
Rev. 1.1
C8051F55x/56x/57x
SFRPAGE
SFRNEXT
SFRLAST
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