C8051F340/1/2/3/4/5/6/7
SFR Definition 17.2. SMB0CN: SMBus Control
R | R | R/W | R/W | R | R | R/W | R/W | Reset Value |
MASTER TXMODE
STA
STO
ACKRQ ARBLOST
ACK
SI
00000000
Bit7 | Bit6 | Bit5 | Bit4 | Bit3 | Bit2 | Bit1 | Bit0 | Bit | |
Addressable | |||||||||
|
|
|
|
|
|
|
| ||
|
|
|
|
|
| SFR Address: 0xC0 | |||
Bit7: | MASTER: SMBus Master/Slave Indicator. |
|
|
|
| ||||
| This |
|
| ||||||
| 0: SMBus operating in Slave Mode. |
|
|
|
|
| |||
| 1: SMBus operating in Master Mode. |
|
|
|
|
| |||
Bit6: | TXMODE: SMBus Transmit Mode Indicator. |
|
|
|
| ||||
| This |
| |||||||
| 0: SMBus in Receiver Mode. |
|
|
|
|
| |||
| 1: SMBus in Transmitter Mode. |
|
|
|
|
| |||
Bit5: | STA: SMBus Start Flag. |
|
|
|
|
|
| ||
| Write: |
|
|
|
|
|
|
| |
| 0: No Start generated. |
|
|
|
|
|
| ||
| 1: When operating as a master, a START condition is transmitted if the bus is free (If the bus | ||||||||
| is not free, the START is transmitted after a STOP is received or a timeout is detected). If | ||||||||
| STA is set by software as an active Master, a repeated START will be generated after the | ||||||||
| next ACK cycle. |
|
|
|
|
|
|
| |
| Read: |
|
|
|
|
|
|
| |
| 0: No Start or repeated Start detected. |
|
|
|
|
| |||
| 1: Start or repeated Start detected. |
|
|
|
|
| |||
Bit4: | STO: SMBus Stop Flag. |
|
|
|
|
|
| ||
| Write: |
|
|
|
|
|
|
| |
| 0: No STOP condition is transmitted. |
|
|
|
|
| |||
| 1: Setting STO to logic 1 causes a STOP condition to be transmitted after the next ACK | ||||||||
| cycle. When the STOP condition is generated, hardware clears STO to logic 0. If both STA | ||||||||
| and STO are set, a STOP condition is transmitted followed by a START condition. |
| |||||||
| Read: |
|
|
|
|
|
|
| |
| 0: No Stop condition detected. |
|
|
|
|
| |||
| 1: Stop condition detected (if in Slave Mode) or pending (if in Master Mode). |
| |||||||
Bit3: | ACKRQ: SMBus Acknowledge Request |
|
|
|
| ||||
| This | ||||||||
| bit to be written with the correct ACK response value. |
|
|
| |||||
Bit2: | ARBLOST: SMBus Arbitration Lost Indicator. |
|
|
|
| ||||
| This | ||||||||
| transmitter. A lost arbitration while a slave indicates a bus error condition. |
|
| ||||||
Bit1: | ACK: SMBus Acknowledge Flag. |
|
|
|
|
| |||
| This bit defines the | ||||||||
| ten each time a byte is received (when ACKRQ=1), or read after each byte is transmitted. | ||||||||
| 0: A "not acknowledge" has been received (if in Transmitter Mode) OR will be transmitted (if | ||||||||
| in Receiver Mode). |
|
|
|
|
|
| ||
| 1: An "acknowledge" has been received (if in Transmitter Mode) OR will be transmitted (if in | ||||||||
| Receiver Mode). |
|
|
|
|
|
| ||
Bit0: | SI: SMBus Interrupt Flag. |
|
|
|
|
|
| ||
| This bit is set by hardware under the conditions listed in Table 17.3. SI must be cleared by | ||||||||
| software. While SI is set, SCL is held low and the SMBus is stalled. |
|
|
202 | Rev. 0.5 |