Quatech MPAP-100 user manual Baud Rate Generator Programming, SCC Data Encoding Methods

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9.2Baud Rate Generator Programming

9.2Baud Rate Generator Programming

The baud rate generator (hereafter referred to as the BRG) of the SCC consists of a 16-bit down counter, two 8-bit time constant registers, and an output divide-by-two. The time constant for the BRG is programmed into WR12 (least significant byte) and WR13 (most significant byte). The equation relating the baud rate to the time constant is given below while Table 5 shows the time constants associated with a number of popular baud rates when using the standard MPAP-100 9.8304 MHz clock.

Clock_Frequency

Time_Const ￿ 2 ￿ Baud_Rate ￿ Clock_Mode ￿ 2

Where:

Clock_Frequency = 9.8304 x 106

 

 

Clock_Mode = 1, 16, 32, or 64

 

 

Baud_Rate = desired baud rate

 

 

Baud Rate

 

Time Constant

 

 

 

38400

 

126

007E (hex)

 

19200

 

254

00FE (hex)

 

9600

 

510

01FE (hex)

 

4800

 

1022

03FE (hex)

 

2400

 

2046

07FE (hex)

 

1200

 

4094

0FFE (hex)

 

600

 

8190

1FFE (hex)

 

300

 

16382

3FFE (hex)

 

(for Clock_Frequency = 9.8304

MHz )

Table 5 --- time constants for common baud rates

9.3SCC Data Encoding Methods

The SCC provides four different data encoding methods, selected by bits 6 and 5 in WR10. These four include NRZ, NRZI, FM1 and FM0. The SCC also features a digital phase-locked loop (DPLL) that can be programmed to operate in NRZI or FM modes. Also, the SCC contains two features for diagnostic purposes, controlled by bits in WR14. They are local loopback and auto echo.

For further information on these subjects or any others involving the SCC contact Zilog for a complete technical manual.

9.4Support for SCC Channel B

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Contents Users Manual MPAP-100 RS-232 PCMCIA SYNCHRONOUS ADAPTERfor PCMCIA Card Standard compatible machines QUATECH, INCMPAP-100 WARRANTY INFORMATIONPRODUCT DESCRIPTION Single Channel PCMCIA RS-232-D Synchronous Communications AdapterCopyright 2001 Quatech, Inc 5.3 OS/2 Client Driver Configuration Examples 5.2.1 Tying a configuration to a particular socket5.4 Monitoring The Status Of PCMCIA Cards Table of Contents10.3.1 Using channel A for both transmit and receive Table of ContentsAccessing the SCC while FIFOs are enabled 22.1.4 Older Versions of Card and Socket Services1.1 System Requirements 1 Introduction2 Hardware Installation 3 DOS / Windows 3.x Software Installation 3.1.1 DOS client driver installation 3.1 MPAP-100 Client Driver for DOSDEVICE=drive\path\MPAP1CL.SYS S#,B#,I#,C ... S#,B#,I#,C 3.1.3 Hot Swapping 3.1.2 Auto Fallback configurationPage DEVICE=C\MPAP-100\MPAP1CL.SYS 3.2 DOS Client Driver examplesDEVICE=C\MPAP-100\MPAP1CL.SYS b300,c DEVICE=C\MPAP-100\MPAP1CL.SYS s0,b300,i53.3.1 DOS Enabler Installation 3.3 MPAP-100 Enabler for DOS3.3.3 Configuring a card 3.3.2 Hot Swapping is not supportedMPAP1EN S#,B#,I#,W#,C MPAP1EN S#,R,W# 3.3.4 Releasing a cards configurationMPAP1EN.EXE s0,b300,i5,c 3.4 DOS Enabler ExamplesMPAP1EN.EXE s1,b300,i3,wd8 MPAP1EN.EXE s0,r4.1 Using the Add New Hardware Wizard 4 Windows 95/98 InstallationPage Page 4.2 Viewing Resources with Device Manager 4.3 Configuration Options 5.2 OS/2 Client Driver Installation 5 OS/2 Software Installation5.1 System Requirements DEVICE=drive\path\MPAP100.SYS addr,irq,C ... addr,irq,C5.2.3 Hot Swapping 5.2.2 Auto Fallback configurationDEVICE=C\MPAP-100\MPAP100.SYS 300,5 5.5 Installing OS/2 PCMCIA SupportPage 6 Using the MPAP-100 with Syncdrive 7 Addressing 8 Interrupts SDLC/HDLC Bit Synchronous Communications 9 SCC General InformationByte-oriented Synchronous Communications Asynchronous Communications9.1 Accessing the registers Example 3 Write data into the transmit buffer of channel A coding, CRC reset Master interrupt control and resetInterrupt control, Wait/DMA request control Interrupt vector9.3 SCC Data Encoding Methods 9.2 Baud Rate Generator Programming9.4 Support for SCC Channel B ClockFrequency TimeConst 2 BaudRate ClockMode9.4.4 Other signals are not used 9.4.1 Receive data and clock signals9.4.2 Extra clock support for channel A 9.4.3 Extra handshaking for channel A9.5 SCC Incompatibility Warnings 9.5.1 Register Pointer Bits9.5.2 Software Interrupt Acknowledge 10 FIFO Operation 10.2 Accessing the FIFOs10.1 Enabling and disabling the FIFOs 10.2.1 Transmit FIFO10.2.2 Receive FIFO 10.3 SCC configuration for FIFO operationRegister 10.3.2 Using channel B for receive 10.4.1 Interrupt status 10.4 FIFO status and control10.5 Accessing the SCC while FIFOs are enabled 10.4.2 Resetting the FIFOs10.4.3 Reading current FIFO status 10.4.4 Controlling the FIFOsPage 10.7 Receive FIFO timeout SWSYNC 11 Communications RegisterRCKEN --- Receive Clock Source Bit 2 TCKEN --- Transmit Clock SourceBits 1-0 Reserved, always INTS1, INTS0 --- Interrupt Source and Enable Bits 12 Configuration RegisterFIFOEN --- External data FIFO enable External Data FIFOs Present --- Reserved, alwaysRXSRC --- Receive FIFO DMA Source 13 Interrupt Status Register 14 FIFO Status Register 15 FIFO Control Register Bits 7-0 Receive Pattern CharacterThis is 16 Receive Pattern Character RegisterBits 7-0 Receive Pattern Count 17 Receive Pattern Count Register18 Receive FIFO Timeout Register Bit 6 Reserved, always Bits 5-0 Timeout IntervalBit 7 X16MODE --- Clock Mode 19 External Connections 19.2 RING pin 19.1 SYNCA pin19.3 Null-modem cables CIRCUIT AB - SIGNAL GROUND 20 DTE Interface SignalsCIRCUIT BB - RECEIVED DATA CIRCUIT CB - CLEAR TO SENDCIRCUIT CD - DTE READY DATA TERMINAL READY CONNECTOR NOTATION DTR CIRCUIT CC - DCE READY DATA SET READY CONNECTOR NOTATION DSRCIRCUIT CE - RING INDICATOR CONNECTOR NOTATION RING CIRCUIT CF - RECEIVED LINE SIGNAL DETECT CARRIER DETECTCIRCUIT TM - TEST MODE 21 Specifications 22.1.3 Multiple Configuration Attempts 22 Software Troubleshooting22.2 DOS Enabler 22.1 DOS Client Driver 22.1.1 Generic SuperClient Drivers22.2.2 Socket Numbers 22.2.1 With Card and Socket Services22.2.3 Memory range exclusion 22.3 OS/2 Client Driver 22.3.1 Resources Not AvailablePage MPAP-100 Users Manual Revision March P/N