C8051F321-GMR Datasheet, PDF (245/250 Pages) Silicon Laboratories – Full Speed USB, 16 k ISP FLASH MCU Family

C8051F320/1
21. C2 Interface
C8051F320/1 devices include an on-chip Silicon Labs 2-Wire (C2) debug interface to allow Flash program-
ming and in-system debugging with the production part installed in the end application. The C2 interface
uses a clock signal (C2CK) and a bi-directional C2 data signal (C2D) to transfer information between the
device and a host system. See the C2 Interface Specification for details on the C2 protocol.
21.1. C2 Interface Registers
The following describes the C2 registers necessary to perform Flash programming through the C2 inter-
face. All C2 registers are accessed through the C2 interface as described in the C2 Interface Specification.
C2 Register Definition 21.1. C2ADD: C2 Address
Reset Value
00000000
Bit7
Bit6
Bit5
Bit4
Bit3
Bit2
Bit1
Bit0
Bits7–0: The C2ADD register is accessed via the C2 interface to select the target Data register for
C2 Data Read and Data Write commands.
Address
0x00
0x01
0x02
0xB4
Description
Selects the Device ID register for Data Read instructions
Selects the Revision ID register for Data Read instructions
Selects the C2 Flash Programming Control register for Data
Read/Write instructions
Selects the C2 Flash Programming Data register for Data
Read/Write instructions
C2 Register Definition 21.2. C2 Device ID
Reset Value
00001001
Bit7
Bit6
Bit5
Bit4
Bit3
Bit2
Bit1
Bit0
This read-only register returns the 8-bit device ID: 0x09 (C8051F320/1).
Rev. 1.4
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