Quatech RS-422/485 manual

MPA-200/300 RS-422/485 SYNCHRONOUS ADAPTER CARD for ISA compatible machines User's Manual QUATECH, INC. TEL: (330) 655-9000 5675 Hudson Industrial Parkway FAX: (330) 655-9010 Hudson, Ohio 44236 http://www.quatech.com INTERFACE CARDS FOR IBM PC/AT AND PS/2[...]

[...]

Warranty Information Quatech Inc. warrants the MPA-200/300 to be free of defects for one (1) year from the date of purc hase. Quatech I nc. will repair or replace any adapter that fails to perform under nor mal operating conditions and in accordance with the procedures outlined in this document during the warranty period. Any damage that results fr[...]

The information contained in this doc ument cannot be reproduced in any form without the written consent of Quatech, In c. L ikewise, any software programs that might accompany this document can be used only in accordance with any license agreement(s) bet ween the purchaser and Quatech, Inc. Quatech, Inc. reserves the right to change this documen t[...]

Compliances - Electromagnetic Emissions EC - Council Directive 89/336/EEC This equipment has been tested and found to comply with the limits of the following standards for a digital device:  EN50081-1 (EN55022, EN60555-2, EN60555-3)  EN50082-1 (IEC 801-2, IEC 801-3, IEC 801-4) Type of Equipment: Information Technology Equipment Equipment Clas[...]

TABLE OF CONTENTS 37 13 SPECIFICATIONS ................................... 33 12 DEFINITION OF INTERFACE SIGNALS ........... 32 11.2 Null-Modem Cables ................................... 32 11.1 MPA-200 and EIA-530 Compatibility .................... 29 11 EXTERNAL CONNECTIONS ........................ 27 10.2 DCE Configuration ......................[...]

3 Quatech Inc., MPA-200/300 Manual[...]

1 INTRODUCTION The Quatech MPA-200/300 is a single ch annel, sy nchronous serial communica- tion port for sy stems utilizing the architec ture of the I BM AT personal or compati- ble computers. The MPA-200 is RS-422 compatible. The MPA-300 has RS-485 data line driv ers and receivers in place of the MPA-200's RS-422 drivers and receivers. The M[...]

Figure 1 MPA-200 board drawing Quatech, Inc. MPA-200 U1 U2 SW 1 SW 2 U3 U4 U5 U6 U7 U8 X1 U16 U9 U10 U11 U12 U13 U14 U15 U21 U17 J10 J11 J5 J6 J4 CN2 CN1 U22 U23 U26 U18 U19 U20 U25 J8 J7 U29 U24 U28 3 Quatech Inc., MPA-200/300 Manual[...]

2 HARDWARE INSTALLATION I f the default address a nd interrupt settings are sufficient, the MPA-200 can be quickly installed and put to use. The fa ctory default settings ar e listed below in Table 1. Table 1 Default Board Confi guration DMA/DRQ 1 DMA/DRQ 3 IRQ 5 300 hex RxDMA TxDMA Interrupt Address 1. If the default settings are correct, skip to [...]

3 SCC GENERAL INFORMATION The Serial Communications Controlle r (SCC) is a dual channe l, multi-protocol data communications peripheral. The MPA-200 provides a sing le channel for communications, howeve r, to provide full DMA capabilitie s, both channels of the SCC can be utilized. The SCC ca n be softwa re config ured to satisfy a wide variety of [...]

3.1 Accessing the registers The mode of communication desired is es tablished and monitored through the bit values of the internal read and writ e registers. The register set of the SCC includes 16 write registers and 9 read reg isters. These registers only occupy four address locations, which start at the MPA-200's phy sical base address that[...]

Example 3: Write data into the transmit buffer of channel A. mov dx,base ; load base address out dx,al ; write data in ax to buffer Example 4: Read data from the receive buffer of channel A. mov dx,base ; load base address in al,dx ; write data in ax to buffer Table 2 SCC read register description. External/Status interrupt information RR15 Upper b[...]

clock (TCLK) and the RTXC pin for its receive clock (RCL K). Programming of the clocks should be done before enab ling the receiver, transmitter, BRG, or DPLL. Table 3 SCC write register description. External/Status interrupt control WR15 Miscellaneous control bits: baud rate generator, DPLL control, auto echo WR14 Lower byte of baud rate time cons[...]

3.2 Baud Rate Generator Programming The baud rate generator (hereafter referred to as t he BRG) of the SCC consist s of a 16-bit down counter, two 8-b it time constant registers, and an output divide-by - two. The time constant f or the BRG is prog rammed into WR12 (lea st signific ant by te) a nd WR13 (most sig nificant by te). The equa tion relat[...]

3.3 SCC Data Encoding Methods The SCC provides four differe nt data encoding methods, selected by bits D6 and D5 in WR10. These four include NRZ, NRZI , FM1 and FM0. The SCC also features a digital phase-loc ked loop (DPL L) that can be prog rammed to operate in NRZI or FM mode. Also, the SCC contai ns two features for diagnostic purposes, controll[...]

4 JUMPER BLOCK CONFIGURATIONS The MPA-200 utilizes seven user-selectable jumper blocks , that allow the user more flexibility when configuring the board. The f ollowing section explains the function of each of the jumper blocks on the MPA-200. 4.1 J4 - Interrupt Configuration J4 is a three pin jumper which dete rmin es whether or not a board’s in[...]

5&10 IRQ15 4&9 IRQ14 3&8 IRQ12 2&7 IRQ11 1&6 IRQ10 4.3 J10 - Transmit DMA Channel Selection J10 selects the DMA channel to be used f or transmit DMA. Three channels (1 - 3) are available on the MPA-200 for DMA. When selecting a DMA channel, both the DMA acknowledge (DACK) and the DM A request (DRQ) for the appropriate channel ne[...]

4.4 J11 - Receive DMA Channel Selection J11 selects t he DMA channel to be used for receive DMA. Three channels (1 - 3) are available on the MPA-200 for DMA. When selecting a DMA channel, both the DMA acknowledge (DACK) and the DM A request (DRQ) for the appropriate channel need to be selected. Table 9 su mmarizes the jumper bloc k selec tions for [...]

Table 10 Jumper block J7 connections 5&6 Receiver controlled by Comm. Register 4&5 Receiver Always Enabled 2&3 Transmitter controlled by Comm. Register 1&2 Transmitter Always Enabled Pins Driver Control Function 4.6 J8 - SYNCA to RLEN control J8 controls the sig nal pa th from the RL EN bit in the Communica tions reg ister to the SY[...]

5 ADDRESSING The MPA-200 occupies a continuous 8 byte block of I /O addresses. For ex ample, if the base address is set to 300H, then the MPA-200 will occupy address locations 300H-307H. The base address of the MPA-200 ma y be set to any of the first 64 Kby tes (0 - FFFFH) of available I / O addre ss space through the setting s of dip switches SW1 [...]

The first four by tes, Base+0 throug h Base+3, of address space on the MPA-200 contain the internal registers of the SCC. The nex t two locations Base+4 and Base+5 contain t he communica tions register and the conf ig uration register. The last two address port locat ions are reserved for future use. The entire address range of the MPA-200 is shown[...]

6 INTERRUPTS The MPA-200 supports eleven interrupt leve ls: IRQ2 -7, I RQ10 - 12, and I RQ14 - 15. The interrupt level is selected th rough jumper blocks J5 and J6 ( see JUMPER BLOCK CONFIGURATI ONS on page 11). The interrupt source is selected by bits D4 and D5 of the c onfiguration register. The MPA-200 has three interrupt sources: interrupt on t[...]

7 DIRECT MEMORY ACCESS Direct Memory Access (DMA) is a way of directly transferring data to and from memory , resulting in hig h data transf er r ates with very low CPU overhead. The MPA-200 allows the user to perform DM A transfers when data is received (DMARRQ) or when da ta is transmitted (DMATRQ). Thre e differe nt DMA channels are avai lable(D[...]

of the SCC, a DMA reque st is ge nerated. The DMA contr oller then writes the data from the SCC into memory. Programming for DMA request on both trans mit and receive is simply a combina- tion of the two. There are three possible c onfigurations that can be used, depend- ing on the sources selected. The first configuration available uses the W/R EQ[...]

Figure 3 Block diagram of DMA on MPA-200. W/ R E Q A DTR/REQA W/ R E Q B SCC DMATRQ DRMRRQ J10 J11 PAL 7.1 Using Terminal Count to Generate an Interrupt The MPA-200 allows the option of generatin g an interrupt whenever the Terminal Count (TC) signal is asserted. Terminal Count is an indicator ge nerated by the sy stem’s DMA controller, which sig[...]

8 CONFIGURATION REGISTER The MPA-200 is equipped with an onboard re gister used for configuring informa- tion such as DMA enables, DMA sources, in terrupt enables, and interrupt sources. Below is a detailed descr ipti on of the configuration regi ster. The address of this register is Base+5. Tabl e 13 de tails the bit definitions of the conf igurat[...]

D1 -RXSRC, RECEIVE DMA SOURCE: When set (logic 1), this bit allows the source for receive DMA to come from the W/REQB pin of channel B on the SCC. When cleared (logic 0), the source for receive DMA comes from the W/REQA pin of channel A on the SCC. D0 -TXSRC, TRANSMIT DMA SOURCE: When set (logic 1), this bit allows the source for transmit DMA to co[...]

9 COMMUNICATIONS REGISTER The MPA-200 is equipped with an onboard communications register which gives the user options pertaining to the clocks and testing. The user can specify the source and type of clock to be transmitted or received. Te st mode bits pertain only to the DTE versions and can be ignored if using a MPA-200 configured DCE. The addre[...]

D3 -RECEIVE CLOCK ENABLE (DCE only): When set (logic 1), this bit allows the DCE to transmit its receive clock (RCLK). When cleared (logic 0), the DCE receives its RCLK. Since a DTE can only receive its RCLK, writing to this bit has no effect on a DTE. D2 -TRANSMIT CLOCK ENABLE (DTE only): When set (logic 1), this bit allows the DTE to transmit its[...]

10 DTE / DCE Configuration The MPA-200 can be purchased in either Data Terminal Equipment (DTE) or Data Communications Equipment (DCE) configuration. The two config urations share some important features, but have si gnificant differences whi ch need to be mentioned. Both the DTE and DCE config urations allow the user to enable and disable the driv[...]

10.1 DTE Configuration The control signals that the DTE can generate are the Request To Send (RTS) and Data Terminal Ready (DTR). I t can receive the signals Carrier Detect (CD), Clear to Send (CTS) , and Data Set Re ady (DSR). All of the control sig nals ar e controlled through channel A of the SCC, with the ex ception of the DSR signal, which is [...]

10.2 DCE Configuration On the MPA-200, the difference between th e DTE and DCE signals is that, with the except ion of a few control signals, the pins used for signal transmission on the DTE are used for signal reception on the DCE and vice versa. For example, pin 2 of the DCE connector is received data, y et the corresponding DTE signal is the tra[...]

Figure 3 DCE Clock Configuration TRX CA RTXCA RTXCB RRCLK RTCLK TRX CB RCKEN TTCLK TCKEN (RCLK) (TCLK ) The Test Mode (TM) signal is always in the OFF condition and cannot be changed by the user. The L o cal Loopback (L L) and Remote L oopback (RL) test sig nals are not implemented on the DCE. Table 16 summarizes the signals on the DCE. Quatech Inc[...]

11 EXTERNAL CONNECTIONS When configured as a DTE, the MPA- 200 uses a D-25 short body male connector (labeled CN2). When configured as a DCE, the MPA-200 uses a D-25 long body female connector (labeled CN1). Tabl e 15 and Table 16 describe the pin out definitions for both connectors a nd Fig ure 6 and Figure 7 illustrate the pin-outs for each of th[...]

Table 16 DCE Connector Pin Definitions Always Zero TEST MODE 25 TRXC +RRCLK 24 DCDA -DSR 23 DTR/REQA -DTR 22 No Connect 21 DCDA +DSR 20 CTSA -CTS 19 No Connect 18 TRXCA +TTCLK 17 TXDA -TXD 16 TRXCB +RTCLK 15 RXDA -RXD 14 RTSA -RTS 13 TRXCB -RTCLK 12 RTXC -RRCLK 11 DTR/REQB -CD 10 TRXCA -TTCLK 9 DTR/REQB +CD 8 DGND 7 DTR/REQA +DTR 6 RTSA +RTS 5 CTSA[...]

Figure 4 MPA-200 DTE Output Connector 25 TEST MODE 24 +TTCLK 23 -DTR 22 -DSR 21 RLBK 20 +DTR 19 -RTS 18 LLBK 17 +RRCLK 16 -RX D 15 +RTCLK 14 -TXD CGND 1 +TXD 2 +RXD 3 +RTS 4 +CTS 5 +DSR 6 DGND 7 +CD 8 -RRCLK 9 -CD 10 -TTCLK 11 -RTCLK 12 -CTS 1 3 Figure 5 MPA-200 DCE Output Connector 25 TEST MODE 24 +RRCLK 23 -DSR 22 -DTR 21 N/C 20 +DSR 19 -CTS 18 N[...]

11.1 MPA-200 and EIA-530 Com patibility I f the MPA-200 is to be connected with an EI A-530 device, it may be necessary to swap the +/- conductors on the TXD and RXD signals. 11.2 Null-Modem Cables The MPA-200 does not use a standard asyn chronous PC serial port connector pin out. Typical off-the-shelf null-modem cables cannot be used with this car[...]

12 DEFINITION OF INTERFACE SIGNALS CIRCUIT AB - SIGNAL GROUND  CONNECTOR NOTATION: DGND  DIRECTION: Not applicable This conductor directly connects the DTE circuit ground to the DCE circuit ground. CIRCUIT CC - D ATA SET READY (DSR)  CONNECTOR NOTATION: +D SR,-DSR  DIRECTION: From DCE This signal indicates the status of the local DCE by[...]

CIRCUIT DB - TRANSMIT ELEMENT TIMING (TxClk - DCE Source)  CONNECTOR NOTATION: +RTCLK,-RTCLK  DIRECTION: From DCE This signal, generated by the DCE, provides the DTE with element timing information pertaining to the data transmitted to the DCE. CIRCUIT DD - RECEIVER ELEMENT TIMING (RxClk - DCE Source)  CONNECTOR NOTATION: +RRCLK,-RRCLK [...]

CIRCUIT CD - DTE READY (DTR)  CONNECTOR NOTATION: +DTR,-DTR  DIRECTION: To DCE This signal controls the switching of the DCE to the communication channel. The DTE will generate this signal to prepare the DCE to be connected to or removed from the communication channel. CIRCUIT LL - LOCAL LOOPBACK (LL)  CONNECTOR NOTATION: LLBK  DIRECTIO[...]

CIRCUIT TM - TEST MODE (TM)  CONNECTOR NOTATION: TEST MODE  DIRECTION: From DCE This signal indicates to the DTE that the DCE is in a test condition. The DCE generates this signal when it has received a local loopback or remote loopback signal from the DTE. Quatech Inc., MPA-200/300 Manual 36[...]

13 SPECIFICATIONS Bus interface: IBM AT 16-bit bus Controller: Serial Communications Controller, 6 MHz (determined by user, typically an Intel 82530). Physical Dimensions: 7.65” x 4.2” Interface: DTE: male D-25 connector DCE: female D-25 connector Transmit drivers: EIA-422: MC3487 or compatible EIA-423: MC3488 or compatible EIA-485: 75174 or co[...]

MPA-200/300 User's Manual Version 5.31 March 2004 Part No. 940-0038-531[...]