SNIU028D February 2016 – September 2020 UCD3138 , UCD3138064 , UCD3138064A , UCD3138128 , UCD3138A , UCD3138A64
Address FFF7618
30 | 29 | 23 |
SLAVE_ADDR_2_EN* | SLAVE_ADDR_2* |
R/W-0 | R/W-110 0000 |
22 | 21 | 20 | 19 | 18 | 16 |
RX_BYTE_ACK_CNT | MAN_CMD | TX_PEC | TX_COUNT |
R/W-11 | R/W-0 | R/W-0 | R/W-000 |
15 | 14 | 8 | 7 | 6 | 0 |
PEC_ENA | SLAVE_MASK | MAN_SLAVE_ACK | SLAVE_ADDR |
R/W-0 | R/W-111 1111 | R/W-0 | R/W-111 1100 |
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset |
Bit | Field | Type | Reset | Description |
---|---|---|---|---|
30 | SLAVE_ADDR_2_EN* | R/W | 0 | Enable auto detection of the 2nd slave address. 0 = 2nd slave address disabled (default) 1 = 2nd slave address enabled *Only available on UCD3138A64 and UCD3138128 A and non-A versions |
29-23 | SLAVE_ADDR_2* | R/W | 110 0000 | Configures the second device address of the slave. Used in automatic slave address acknowledge mode (default mode). *Only available on UCD3138A64 and UCD3138128 A and non-A versions) |
22-21 | RX_BYTE_ACK _CNT | R/W | 11 | Configures number of data bytes to automatically acknowledge when receiving data in slave mode. 00 = 1 byte received by slave. Firmware is required to manually acknowledge every received byte. 01 = 2 bytes received by slave. Hardware automatically acknowledges the first received byte. Firmware is required to manually acknowledge after the second received byte. 10 = 3 bytes received by slave. Hardware automatically acknowledges the first 2 received bytes. Firmware is required to manually acknowledge after the third received byte. 11 = 4 bytes received by slave. Hardware automatically acknowledges the first 3 received bytes. Firmware is required to manually acknowledge after the fourth received byte (Default) |
20 | MAN_CMD | R/W | 0 | Manual Command Acknowledgement Mode 0 = Slave automatically acknowledges received command code (Default) 1 = Data Request flag generated after receipt of command code, firmware required to issue ACK to continue message |
19 | TX_PEC | R/W | 0 | Asserted when the slave needs to send a PEC byte at end of message. PMBus Interface will transmit the calculated PEC byte after transmitting the number of data bytes indicated by TX Byte Cnt(Bits 19:17). 0 = No PEC byte transmitted (Default) 1 = PEC byte transmitted at end of current message |
18-16 | TX_COUNT | R/W | 000 | Number of valid bytes in Transmit Data Register 0 = No bytes valid (Default) 1 = One byte valid, Byte #0 (Bits 7:0 of Receive Data Register) 2 = Two bytes valid, Bytes #0 and #1 (Bits 15:0 of Receive Data Register) 3 = Three bytes valid, Bytes #0-2 (Bits 23:0 of Receive Data Register) 4 = Four bytes valid, Bytes #0-3 (Bits 31:0 of Receive Data Register) |
15 | PEC_ENA | R/W | 0 | PEC Processing Enable 0 = PEC processing disabled (Default) 1 = PEC processing enabled |
14-8 | SLAVE_MASK | R/W | 111 1111 | Used in address detection, the slave mask enables acknowledgement of multiple device addresses by the slave. Writing a ‘0’ to a bit within the slave mask enables the corresponding bit in the slave address to be either ‘1’ or ‘0’ and still allow for a match. Writing a ‘0’ to all bits in the mask enables the PMBus Interface to acknowledge any device address. Upon power-up, the slave mask defaults to 7Fh, indicating the slave will only acknowledge the address programmed into the Slave Address (Bits 6-0). |
7 | MAN_SLAVE _ACK | R/W | 0 | Manual Slave Address Acknowledgement Mode 0 = Slave automatically acknowledges device address specified in SLAVE_ADDR, Also uses SLAVE_ADDR_2 if present and enabled. (Default) 1 = Enables the Manual Slave Address Acknowledgement Mode. Firmware is required to read received address and acknowledge on every message |
6-0 | SLAVE_ADDR | R/W | 111 1100 | Configures the current device address of the slave. Used in automatic slave address acknowledge mode (default mode). The PMBus Interface will compare the received device address with the value stored in the Slave Address bits and the mask configured in the Slave Mask bits. If matching, the slave will acknowledge the device address. |