Table 6-89 Switching Characteristics Over Recommended Operating Conditions for UARTx Transmit(1)
(see Figure 6-45)
NO. |
PARAMETER |
1.3V, 1.2V, 1.1V, 1.0V |
UNIT |
MIN |
MAX |
1 |
f(baud)
|
Maximum programmable baud rate |
|
D/E (2)(3)
|
MBaud (4)
|
2 |
tw(UTXDB)
|
Pulse duration, transmit data bit (TXDn) |
U - 2 |
U + 2 |
ns |
3 |
tw(UTXSB)
|
Pulse duration, transmit start bit |
U - 2 |
U + 2 |
ns |
(1) U = UART baud time = 1/programmed baud rate.
(2) D = UART input clock in MHz.
For UART0, the UART input clock is SYSCLK2.
For UART1 or UART2, the UART input clock is ASYNC3 (either PLL0_SYCLK2 or PLL1_SYSCLK2).
(3) E = UART divisor x UART sampling rate. The UART divisor is set through the UART divisor latch registers (DLL and DLH). The UART sampling rate is set through the over-sampling mode select bit (OSM_SEL) of the UART mode definition register (MDR).
(4) Baud rate is not indicative of data rate. Actual data rate will be limited by system factors such as EDMA loading, EMIF/DDR loading, system frequency, etc.
Figure 6-45 UART Transmit/Receive Timing