SLLSFE8B November 2024 – November 2025 TCAN2845-Q1 , TCAN2847-Q1
PRODUCTION DATA
The SPI communication uses a standard SPI. Physically the digital interface pins are nCS (Chip Select Not), SDI (SPI Data In), SDO (SPI Data Out) and SCK (SPI Clock). Each SPI transaction is initiated by a seven bit address with a R/W bit. The TCAN284x-Q1 can be configured for one data byte or two date bytes per transaction depending upon the value of the BYTE_CNT bit at SPI_CONFIG register 8'h09[3]. The default is one byte. When two byte is selected, the second data byte is for address + 1.
The data shifted out on the SDO pin for the transaction always starts with the register 8'h50[7:0] which is the global interrupt register. This register provides the high-level interrupt status information about the device. The data byte which are the ‘response’ to the address and R/W byte are shifted out next. See Figure 8-72 and Figure 8-73 for read and write method when cyclic redundancy (CRC) is disabled. For two byte read see Figure 8-75. When a two byte SPI write takes place, the current information in the address and address + 1 is fed back out on the SDO pin, see Figure 8-74.
The device defaults to mode 0 where SPI data input data on SDI is sampled on the low to high edge of SCK. The SPI output data on SDO is changed on the high to low edge of SCK. The device can be configured to support Mode 1 - 3 by using MODE_SEL in SPI_CONFIG register 8'h09[1:0]. SPI communication figures are based upon Mode 0.