C8051F300 Datasheet, PDF (20/176 Pages) List of Unclassifed Manufacturers – Mixed Signal ISP Flash MCU Family

C8051F300/1/2/3/4/5
Perhaps the most unique Port I/O enhancement is the Digital Crossbar. This is essentially a digital switch-
ing network that allows mapping of internal digital system resources to Port I/O pins (See Figure 1.7). On-
chip counter/timers, serial buses, HW interrupts, comparator output, and other digital signals in the control-
ler can be configured to appear on the Port I/O pins specified in the Crossbar Control registers. This allows
the user to select the exact mix of general purpose Port I/O and digital resources needed for the particular
application.
XBR0, XBR1,
XBR2 Registers
P0MDOUT,
P0MDIN Registers
Highest
Priority
Lowest
Priority
2
UART
Priority
Decoder
2
SMBus
CP0
2
Outputs
SYSCLK
Digital
Crossbar
8
PCA
4
2
T0, T1
8
Port Latch P0 _(P0.0-P0.7)
P0
I/O
Cells
P0.0
P0.7
Figure 1.7. Digital Crossbar Diagram
1.5. Serial Ports
The C8051F300/1/2/3/4/5 Family includes an SMBus/I²C interface and a full-duplex UART with enhanced
baud rate configuration. Each of the serial buses is fully implemented in hardware and makes extensive
use of the CIP-51's interrupts, thus requiring very little CPU intervention.
20
Rev. 2.8