C8051F321 Silicon Laboratories Inc, C8051F321 Datasheet - Page 255

• Manufacturer Part Number: C8051F321
• Description: IC 8051 MCU 16K FLASH 28MLP
• Manufacturer: Silicon Laboratories Inc
• Series: C8051F32xr

Specifications of C8051F321

• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 25MHz
• Connectivity: SMBus (2-Wire/I²C), SPI, UART/USART, USB
• Peripherals: Brown-out Detect/Reset, POR, PWM, Temp Sensor, WDT
• Number Of I /o: 21
• Program Memory Size: 16KB (16K x 8)
• Program Memory Type: FLASH
• Ram Size: 2.25K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 3.6 V
• Data Converters: A/D 13x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 28-VQFN Exposed Pad, 28-HVQFN, 28-SQFN, 28-DHVQFN
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -

21.2. C2 Pin Sharing
The C2 protocol allows the C2 pins to be shared with user functions so that in-system debugging, FLASH program-
ming, and boundary scan functions may be performed. This is possible because C2 communication is typically per-
formed when the device is in the halt state, where all on-chip peripherals and user software are stalled. In this halted
state, the C2 interface can safely ‘borrow’ the C2CK (/RST) and C2D (P3.0) pins. In most applications, external
resistors are required to isolate C2 interface traffic from the user application. A typical isolation configuration is
shown in Figure 21.6.
The configuration in Figure 21.6 assumes the following:
Additional resistors may be necessary depending on the specific application.
1.
2.
The user input (b) cannot change state while the target device is halted.
The /RST pin on the target device is used as an input only.
/Reset (a)
Output (c)
Input (b)
Figure 21.6. Typical C2 Pin Sharing
C2 Interface Master
Rev. 1.1
C2CK
C2D
C8051Fxxx
C8051F320/1
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