SNVSC07A June 2021 – September 2022 LP876242-Q1
PRODUCTION DATA
The device supports SPI serial-bus interface and it operates as a peripheral device. The MCU in the system acts as the controller device. A single read and write transmission consists of 24-bit write and read cycles (32-bit if CRC is enabled) in the following order:
In parallel with ADDR[7:0], PAGE[2:0], Read/Write definition and RESERVED[3:0] bits the device sends 16-bit interrupt status using SDO_SPI pin in the following order:
The status signals are in INT_SPI_STATUS register:
EN_DRV_STAT bit is showing the live state of the EN_DRV pin, whereas all other status bits are latched in the same way as interrupts indicated with nINT pin. The latched status bits in INT_SPI_STATUS register are cleared by writing 1 to the latched bit. Bits 10-16 are sent for redundancy for bits 2-8 with opposite polarity. Bits 10-16 are always correlating with bits 2-8 and do not change during communication even when the status signal changes.
The embedded CRC filed can be enabled or disabled from the protocol by setting the I2C1_SPI_CRC_EN register bit to '1' - enabled, '0' - disabled. The default of this bit is configurable through the NVM.
The SDO_SPI output is in a high-impedance state when the CS_SPI pin is high. When the CS_SPI pin is low, the SDO_SPI output is always driven low except when the RDATA or SCRC bits are sent. When the RDATA or SCRC bits are sent, the SDO_SPI output is driven accordingly.
The address, page, data, and CRC are transmitted MSB first. The chip-select signal (CS_SPI) must be low during the cycle transmission. The CS_SPI signal resets the interface when it is high, and must be taken high between successive cycles. Data is clocked in on the rising edge of the SCK_SPI clock signal and it is clocked out on the falling edge of SCK_SPI clock signal.
The SPI Timing diagram shows the timing information for these signals.