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Acrosser AR-B1550 User Manual

Page 12

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AR-B1550 User

s Guide

10

(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

(7) Line Status Register (LSR)

Bit 0: Data Ready (DR)
Bit 1: Overrun Error (OR)
Bit 2: Parity Error (PE)
Bit 3: Framing Error (FE)
Bit 4: Break Interrupt (BI)
Bit 5: Transmitter Holding Register Empty (THRE)
Bit 6: Transmitter Shift Register Empty (TSRE)
Bit 7: Must be 0

(8) MODEM Status Register (MSR)

Bit 0: Delta Clear to Send (DCTS)
Bit 1: Delta Data Set Ready (DDSR)
Bit 2: Training Edge Ring Indicator (TERI)
Bit 3: Delta Receive Line Signal Detect (DSLSD)
Bit 4: Clear to Send (CTS)
Bit 5: Data Set Ready (DSR)
Bit 6: Ring Indicator (RI)
Bit 7: Received Line Signal Detect (RSLD)

(9) Divisor Latch (LS, MS)

LS

MS

Bit 0:

Bit 0

Bit 8

Bit 1:

Bit 1

Bit 9

Bit 2:

Bit 2

Bit 10

Bit 3:

Bit 3

Bit 11

Bit 4:

Bit 4

Bit 12

Bit 5:

Bit 5

Bit 13

Bit 6:

Bit 6

Bit 14

Bit 7:

Bit 7

Bit 15