USART

Figure 1. USART in SPI Mode - Timing Requirements in Host Mode

Table 1. USART in SPI Host Mode - Timing Specifications
Symbol	Description	Min.	Typ.✝	Max.	Unit
f_SCK *	SCK clock frequency	—	—	10	MHz
T_SCK *	SCK period	100	—	—	ns
t_SCKW	SCK high/low width	—	0.5×T_SCK	—	ns
t_SCKR	SCK rise time	—	2.7	—	ns
t_SCKF	SCK fall time	—	2.7	—	ns
t_MIS	MISO setup to SCK	—	10	—	ns
t_MIH	MISO hold after SCK	—	10	—	ns
t_MOS	MOSI setup to SCK	—	0.5×T_SCK	—	ns
t_MOH	MOSI hold after SCK	—	1.0	—	ns
✝ Data in the “Typ.” column is at T_A = 25°C and V_DD = 3.0V unless otherwise specified. These parameters are for design guidance only and are not tested. * These parameters are characterized but not tested in production.