SC16C754B NXP Semiconductors, SC16C754B Datasheet - Page 14

• Manufacturer Part Number: SC16C754B
• Description: 5 V - 3.3 V and 2.5 V quad UART - 5 Mbit/s (max.)
• Manufacturer: NXP Semiconductors

NXP Semiconductors
SC16C754B_4
Product data sheet
6.4 Reset
UART1 begins transmission and sends 52 characters, at which point UART2 will generate
an interrupt to its processor to service the RX FIFO, but assumes the interrupt latency is
fairly long. UART1 will continue sending characters until a total of 60 characters have
been sent. At this time, UART2 will transmit a 0Fh to UART1, informing UART1 to halt
transmission. UART1 will likely send the 61
character. Now UART2 is serviced and the processor reads enough data out of the RX
FIFO that the level drops to 32. UART2 will now send a 0Dh to UART1, informing UART1
to resume transmission.
Table 4
Table 4.
Remark: Registers DLL, DLM, SPR, Xon1, Xon2, Xoff1, Xoff2 are not reset by the
top-level reset signal RESET, that is, they hold their initialization values during reset.
Table 5
Table 5.
Register
Interrupt enable register
Interrupt identification register
FIFO control register
Line control register
Modem control register
Line status register
Modem status register
Enhanced feature register
Receiver holding register
Transmitter holding register
Transmission control register
Trigger level register
Signal
TX
RTS
DTR
RXRDY
TXRDY
summarizes the state of register after reset.
summarizes the state of registers after reset.
Register reset functions
Signal RESET functions
5 V, 3.3 V and 2.5 V quad UART, 5 Mbit/s (max.) with 64-byte FIFOs
Rev. 04 — 6 October 2008
Reset control
RESET
RESET
RESET
RESET
RESET
RESET
RESET
RESET
RESET
RESET
RESET
RESET
Reset control
RESET
RESET
RESET
RESET
RESET
st
character while UART2 is sending the Xoff
Reset state
all bits cleared
bit 0 is set; all other bits cleared
all bits cleared
reset to 0001 1101 (1Dh)
all bits cleared
bit 5 and bit 6 set; all other bits cleared
bits 3:0 cleared; bits 7:4 input signals
all bits cleared
pointer logic cleared
pointer logic cleared
all bits cleared
all bits cleared
Reset state
HIGH
HIGH
HIGH
HIGH
LOW
SC16C754B
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