Acrosser Technology AR-B1380, User Manual

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AR-B1380/AR-B1380A User’ s Guide
Page 13
(1) Receiver Buffer Register (RBR)
Bit 0-7: Received data byte (Read Only)
(2) Transmitter Holding Register (THR)
Bit 0-7: Transmitter holding data byte (Write Only)
(3) Interrupt Enable Register (IER)
Bit 0: Enable Received Data Available Interrupt (ERBFI)
Bit 1: Enable Transmitter Holding Empty Interrupt (ETBEI)
Bit 2: Enable Receiver Line Status Interrupt (ELSI)
Bit 3: Enable MODEM Status Interrupt (EDSSI)
Bit 4: Must be 0
Bit 5: Must be 0
Bit 6: Must be 0
Bit 7: Must be 0
(4) Interrupt Identification Register (IIR)
Bit 0: “ 0” if Interrupt Pending
Bit 1: Interrupt ID Bit 0
Bit 2: Interrupt ID Bit 1
Bit 3: Must be 0
Bit 4: Must be 0
Bit 5: Must be 0
Bit 6: Must be 0
Bit 7: Must be 0
(5) Line Control Register (LCR)
Bit 0: Word Length Select Bit 0 (WLS0)
Bit 1: Word Length Select Bit 1 (WLS1)
WLS1 WLS0 Word
Length
0 0 5 Bits
0 1 6 Bits
1 0 7 Bits
1 1 8 Bits
Bit 2: Number of Stop Bit (STB)
Bit 3: Parity Enable (PEN)
Bit 4: Even Parity Select (EPS)
Bit 5: Stick Parity
Bit 6: Set Break
Bit 7: Divisor Latch Access Bit (DLAB)
(6) MODEM Control Register (MCR)
Bit 0: Data Terminal Ready (DTR)
Bit 1: Request to Send (RTS)
Bit 2: Out 1 (OUT 1)
Bit 3: Out 2 (OUT 2)
Bit 4: Loop
Bit 5: Must be 0
Bit 6: Must be 0
Bit 7: Must be 0