70592C Datasheet, PDF (178/314 Pages) Microchip Technology – High-Performance, 16-bit Microcontrollers

PIC24HJXXXGPX06A/X08A/X10A
REGISTER 18-2: UxSTA: UARTx STATUS AND CONTROL REGISTER
R/W-0
R/W-0
R/W-0
U-0
R/W-0 HC
R/W-0
UTXISEL1 UTXINV UTXISEL0
—
UTXBRK
UTXEN⁽¹⁾
bit 15
R-0
UTXBF
R-1
TRMT
bit 8
R/W-0
R/W-0
URXISEL<1:0>
bit 7
R/W-0
ADDEN
R-1
RIDLE
R-0
PERR
R-0
FERR
R/C-0
OERR
R-0
URXDA
bit 0
Legend:
R = Readable bit
-n = Value at POR
HC = Hardware cleared
W = Writable bit
‘1’ = Bit is set
C = Clear only bit
U = Unimplemented bit, read as ‘0’
‘0’ = Bit is cleared
x = Bit is unknown
bit 15,13
bit 14
bit 12
bit 11
bit 10
bit 9
bit 8
bit 7-6
UTXISEL<1:0>: Transmission Interrupt Mode Selection bits
11 = Reserved; do not use
10 = Interrupt when a character is transferred to the Transmit Shift Register, and as a result, the
transmit buffer becomes empty
01 = Interrupt when the last character is shifted out of the Transmit Shift Register; all transmit
operations are completed
00 = Interrupt when a character is transferred to the Transmit Shift Register (this implies there is
at least one character open in the transmit buffer)
UTXINV: Transmit Polarity Inversion bit
If IREN = 0:
1 = UxTX Idle state is ‘0’
0 = UxTX Idle state is ‘1’
If IREN = 1:
1 = IrDA^® encoded UxTX Idle state is ‘1’
0 = IrDA^® encoded UxTX Idle state is ‘0’
Unimplemented: Read as ‘0’
UTXBRK: Transmit Break bit
1 = Send Sync Break on next transmission – Start bit, followed by twelve ‘0’ bits, followed by Stop bit;
cleared by hardware upon completion
0 = Sync Break transmission disabled or completed
UTXEN: Transmit Enable bit⁽¹⁾
1 = Transmit enabled, UxTX pin controlled by UARTx
0 = Transmit disabled, any pending transmission is aborted and buffer is reset. UxTX pin controlled
by port.
UTXBF: Transmit Buffer Full Status bit (read-only)
1 = Transmit buffer is full
0 = Transmit buffer is not full, at least one more character can be written
TRMT: Transmit Shift Register Empty bit (read-only)
1 = Transmit Shift Register is empty and transmit buffer is empty (the last transmission has completed)
0 = Transmit Shift Register is not empty, a transmission is in progress or queued
URXISEL<1:0>: Receive Interrupt Mode Selection bits
11 = Interrupt is set on UxRSR transfer making the receive buffer full (i.e., has 4 data characters)
10 = Interrupt is set on UxRSR transfer making the receive buffer 3/4 full (i.e., has 3 data characters)
0x = Interrupt is set when any character is received and transferred from the UxRSR to the receive
buffer. Receive buffer has one or more characters.
Note 1: Refer to Section 17. “UART” (DS70232) in the “dsPIC33F/PIC24H Family Reference Manual” for
information on enabling the UART module for transmit operation.
DS70592C-page 178
© 2011 Microchip Technology Inc.