Sony AR-B1570 manual Serial Port

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AR-B1570 Users Guide

2.5 SERIAL PORT

The ACEs (Asynchronous Communication Elements ACE1 to ACE4) are used to convert parallel data to a serial format on the transmit side and convert serial data to parallel on the receiver side. The serial format, in order of transmission and reception, is a start bit, followed by five to eight data bits, a parity bit (if programmed) and one,

1.5(in a five-bit format only) or two stop bits(in a 6,7, or 8-bit format). The ACEs are capable of handling divisors of 1 to 65535, and produce a 16x clock for driving the internal transmitter logic.

Provisions are also included to use this 16x clock to drive the receiver logic. Also included in the ACE a completed MODEM control capability, and a processor interrupt system that may be software tailored to the computing time required to handle the communications link.

The following table is a summary of each ACE accessible register

DLAB

Port Address

Register

0

base + 0

Receiver buffer (read)

 

 

Transmitter holding register (write)

0

base + 1

Interrupt enable

X

base + 2

Interrupt identification (read only)

X

base + 3

Line control

X

base + 4

MODEM control

X

base + 5

Line status

X

base + 6

MODEM status

X

base + 7

Scratched register

1

base + 0

Divisor latch (least significant byte)

1

base + 1

Divisor latch (most significant byte)

ACE Accessible Registers

(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)

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Contents Industrial Grade CPU Board AR-B1570 User’s Guide Save & Exit Setup Exit Without Saving Preface Static Electricity Precautions Organization1SPECIFICATION OverviewPacking List CPU NS Geode GX1 BGAFeatures Award BiosCPU NS Geode GX1 System Controller MicroprocessorDMA Controller Keyboard Controller Interrupt ControllerInterrupt Controller 1 I/O Port Address Map Hex Range DeviceSSD Port Address MapTimer Real-Time Clock and Non-Volatile RAMAddress Description Real-Time Clock & Non-Volatile RAMSerial Port Modem Control Register MCR Line Status Register LSRModem Status Register MSR Divisor Latch LS, MSParallel Port Register AddressPrinter Interface Logic Data SwapperPrinter Control Latch & Printer Control Swapper Bit’s DefinitionSetting UP the System System SettingOverview External System LocationHard Disk IDE Connector Pin Hard Disk IDE Connector CN8Pin Hard Disk IDE Connector CN7 Pin SignalFDD Port Connector CN3 Hard Disk IDE1 ConnectorFDD Pin Assignment Ethernet RJ-45 Connector LAN1 4 PS/2 KB/Mouse Connector CN4 & PS1Reset Header J7 PS-ON Header CN9Power Connector PWR2 CRT Connector P4LCD Panel Display Connector LCD1 P4 CRT ConnectorUSB ConnectorUSB1 LED Header J8LCD Display Pin Assignment Pin Description13 PC104 Connector Pin PC/104 Connector Bus a & B PC104Pin PC/104 Connector Bus C & D PC104 Parallel Port Connector CN2 16 Ext. Battery CN1Battery Jumper JP2 15 IR. Header J1RS-232 Connector Pin Assignment 18 COM1, COM2 CN5, CN6RS-232/RS-485 Select for COM1 P2 & P3 RS-485 Terminator Select J2Touch Screen Connector J3 & J4 ATX Power External Bottom Connector J620 D.O.C. Memory Address Select JP1 Installation Driver InstallationUtility Diskette Watchdog Timer Watchdog Block DiagramDisk Watchdog Timer Setting Watchdog Timer TriggerIRQ Bios Console Bios Setup OverviewBios Setup Main Menu Standard Cmos Setup Date & Time SetupHard Disk Setup Floppy SetupHalt On EGA/VGAMono Bios Features Setup Typematic Rate Setting Typematic Delay MsecVideo Bios Shadow Memory Parity CheckChipset Features Setup Bit I/O Cycle Recovery TimeChipset Features Setup Sdram CAS latency TimePNP/PCI Configuration Load Default SettingLoad Bios Defaults Load Setup DefaultsIntegrated Peripherals Password Setting Bios ExitIDE HDD Auto Detection