C8051F960-A-GQ Silicon Labs, C8051F960-A-GQ Datasheet - Page 390

• Manufacturer Part Number: C8051F960-A-GQ
• Description: 8-bit Microcontrollers - MCU 128KB DC-DC LCD AES
• Manufacturer: Silicon Labs

Specifications of C8051F960-A-GQ

• Rohs: yes
• Core: 8051
• Processor Series: C8051
• Data Bus Width: 8 bit
• Maximum Clock Frequency: 24.5 MHz
• Program Memory Size: 128 KB
• Data Ram Size: 8 KB
• On-chip Adc: Yes
• Operating Supply Voltage: 1.8 V to 3.8 V
• Operating Temperature Range: - 40 C to + 85 C
• Package / Case: QFP-80
• Mounting Style: SMD/SMT

C8051F96x
28.4.3. Hardware Slave Address Recognition
The SMBus hardware has the capability to automatically recognize incoming slave addresses and send an
ACK without software intervention. Automatic slave address recognition is enabled by setting the EHACK
bit in register SMB0ADM to 1. This will enable both automatic slave address recognition and automatic
hardware ACK generation for received bytes (as a master or slave). More detail on automatic hardware
ACK generation can be found in Section 28.4.2.2.
The registers used to define which address(es) are recognized by the hardware are the SMBus Slave
Address register (SFR Definition 28.3) and the SMBus Slave Address Mask register (SFR Definition 28.4).
A single address or range of addresses (including the General Call Address 0x00) can be specified using
these two registers. The most-significant seven bits of the two registers are used to define which
addresses will be ACKed. A 1 in bit positions of the slave address mask SLVM[6:0] enable a comparison
between the received slave address and the hardware’s slave address SLV[6:0] for those bits. A 0 in a bit
of the slave address mask means that bit will be treated as a “don’t care” for comparison purposes. In this
case, either a 1 or a 0 value are acceptable on the incoming slave address. Additionally, if the GC bit in
register SMB0ADR is set to 1, hardware will recognize the General Call Address (0x00). Table 28.4 shows
some example parameter settings and the slave addresses that will be recognized by hardware under
those conditions.
390
ARBLOST
MASTER
TXMODE
ACKRQ
STO
ACK
STA
Bit
SI
• A START is generated.
• START is generated.
• SMB0DAT is written before the start of an
• A START followed by an address byte is
• A STOP is detected while addressed as a
• Arbitration is lost due to a detected STOP.
• A byte has been received and an ACK
• A repeated START is detected as a MASTER
• SCL is sensed low while attempting to gener-
• SDA is sensed low while transmitting a 1
• The incoming ACK value is low 
• A START has been generated.
• Lost arbitration.
• A byte has been transmitted and an
• A byte has been received.
• A START or repeated START followed by a
• A STOP has been received.
SMBus frame.
received.
slave.
response value is needed (only when hard-
ware ACK is not enabled).
when STA is low (unwanted repeated START).
ate a STOP or repeated START condition.
(excluding ACK bits).
(ACKNOWLEDGE).
ACK/NACK received.
slave address + R/W has been received.
Table 28.3. Sources for Hardware Changes to SMB0CN
Set by Hardware When:
Rev. 0.5
• A STOP is generated.
• Arbitration is lost.
• A START is detected.
• Arbitration is lost.
• SMB0DAT is not written before the
• Must be cleared by software.
• A pending STOP is generated.
• After each ACK cycle.
• Each time SI is cleared.
• The incoming ACK value is high (NOT
• Must be cleared by software.
start of an SMBus frame.
ACKNOWLEDGE).
Cleared by Hardware When: