Quatech DS-302 User manual

WARRANTY INFORMATION
Quatech Inc. warrants the DS-202/DS-302
to be free of defects for one (1)year from the
date of purchase. Quatech Inc. will repair or replace
any board that fails to perform under normal operating
conditions and in accordance with the procedures
outlined in this document during the warranty period.
Any damage that results from improper installation,
operation, or general misuse voids all warranty rights.
Although every attempt has been made to guarantee
the accuracy of this manual, Quatech Inc. assumes no
liability for damages resulting from errors in this
document. Quatech Inc. reserves the right to edit or
append to this document at any time without notice.
Please complete the following information and
retain for your records. Have this information
available when requesting warranty service.
DATE OF PURCHASE:
MODEL NUMBER: DS-202/DS-302
PRODUCT DESCRIPTION: DUAL CHANNEL RS-422/RS-485
ASYNCHRONOUS COMMUNICATION BOARD
SERIAL NUMBER:
IBMTM, PC/XTTM, PC/ATTM, and PS/2TM are trademarks of
International Business Machines.
i

TABLE OF CONTENTS
WARRANTY INFORMATION . . . . . . . . . . . . i
LIST OF FIGURES . . . . . . . . . . . . . iii
I. INTRODUCTION . . . . . . . . . . . . . . . . 1
II. BOARD DESCRIPTION . . . . . . . . . . . . . 1
III. 16450/16550*FUNCTIONAL DESCRIPTION . . . . 1
INTERRUPT ENABLE REGISTER . . . . . . . . 4
INTERRUPT IDENTIFICATION REGISTER . . . . 5
FIFO CONTROL REGISTER *. . . . . . . . . 7
LINE CONTROL REGISTER . . . . . . . . . . 8
MODEM CONTROL REGISTER . . . . . . . . . 10
LINE STATUS REGISTER . . . . . . . . . . 11
MODEM STATUS REGISTER . . . . . . . . . . 13
SCRATCHPAD REGISTER . . . . . . . . . . . 14
FIFO INTERRUPT MODE OPERATION *. . . . . 14
IV. BAUD RATE SELECTION . . . . . . . . . . . . 14
V. ADDRESSING . . . . . . . . . . . . . . . . . 16
VI. INTERRUPTS . . . . . . . . . . . . . . . . . 18
VII. OUTPUT CONFIGURATIONS . . . . . . . . . . . 19
VIII. EXTERNAL CONNECTIONS . . . . . . . . . . . . 23
IX. INSTALLATION . . . . . . . . . . . . . . . . 24
X. SPECIFICATIONS . . . . . . . . . . . . . . . 24
*with optional 16550.
i

INTRODUCTION
LIST OF FIGURES
Figure 1. DS-202/DS-302 board layout . . . . . . 2
Figure 2. 16450/16550*internal registers . . . 3
Figure 3. Interrupt source identification . . . 6
Figure 4. FIFO receiver trigger levels*. . . . 7
Figure 5. Parity options . . . . . . . . . . . . 9
Figure 6. Word length and stop bit options . . . 9
Figure 7. Input clock frequency selections . . . 15
Figure 8. Divisor latch options . . . . . . . . 15
Figure 9. Address selection switches . . . . . . 16
Figure 10. Address selection examples . . . . . . 17
Figure 11. Channel enable/disable selection . . . 17
Figure 12. System interrupt connection . . . . . 18
Figure 13. Interrupt mode selection . . . . . . . 18
Figure 14. Output control block diagram . . . . . 19
Figure 15. Auxiliary channel jumper definition . 20
Figure 16. Auxiliary channel signal selection . . 21
Figure 17. Half duplex control jumper . . . . . . 21
Figure 18. Output connector definition . . . . . 23
*with optional 16550.
iii

INTRODUCTION
I. INTRODUCTION
The DS-202 is a dual channel RS-422 asynchronous
serial communications adapter for systems implementing
an ISA compatible I/O bus. Data is communicated
through two shielded D-9 connectors which provide
greater shielding from environmental noise. The DS-302
is an RS-485 version of the adapter.
The serial interface is implemented with a pair of
16450 Asynchronous Communication Elements (ACEs). The
16450 is compatible with the 8250 ACE found in the
original IBM PC/XT models. The optional 16550 ACE
provides an additional FIFO mode of operation which
reduces CPU overhead at higher data rates.
The DS-202 / DS-302 allows independent addressing
of each channel through a pair of address decode
switches (SW1 and SW2). These switches allow each
channel to be addressed in the I/O address range 0000H
through 07FFH. Each channel is also capable of
selecting and / or sharing one of six possible
interrupt request lines (IRQ 2,3,4,5,6,7).
II. BOARD DESCRIPTION
A component diagram of the DS-202 / DS-302 showing
the locations of the 16450 ACEs, configuration jumpers,
address selection switches, and output connectors is
shown in figure 1. The first communication channel is
controlled by the ACE labeled U7, switch SW1 for
addressing, jumpers J2 and J5 for interrupt request
selection, jumpers J7 and J8 for output signal control,
and is output through connector CN1. The second
channel is controlled by the ACE labeled U8, switch SW2
for addressing, jumpers J3 and J6 for interrupt request
selection, jumpers J8 and J10 for output signal
control, and is output through connector CN2.
III. 16450/16550FUNCTIONAL DESCRIPTION
The 16450 is an improved specification version of
the 8250 Asynchronous Communications Element (ACE)
found in the original IBM PC and PC/XT systems and is
functionally equivalent to the 8250. This ACE performs
serial-to-parallel conversion on received data and
parallel-to-serial conversion on data output from the
CPU.
iii

Figure 1. DS-202 / DS-302 component layout.

FUNCTIONAL DESCRIPTION
Designed to be compatible with the 16450, the
16550 ACE enters character mode on reset and in this
mode appears as a 16450 to application software. An
additional mode, FIFO mode, can be invoked through
software to reduce CPU overhead by providing two 16-
byte FIFOs (one transmit, one receive) to buffer data
and reduce the number of interrupts issued to the CPU.
Other features of the 16450/16550 include:
Programmable baud rate, character length, parity,
and number of stop bits.
Automatic addition and removal of start, stop, and
parity bits.
Independent and prioritized transmit, receive and
status interrupts.
The following pages provide a brief summary of the
internal registers available within the 16450 and 16550
ACEs. The registers are addressed as shown in figure 2
below. Registers and functions specific to the
optional 16550 are indicated with an asterisk (*).
+---------------+------------------------------+
| DLAB A2 A1 A0 | REGISTER DESCRIPTION |
+---------------+------------------------------+
| 0 0 0 0 | Receive buffer (read only) |
| | Transmit holding register |
| | (writeonly) |
| 0 0 0 1 | Interrupt enable |
| x 0 1 0 | Interrupt identification |
| | (read only) |
| | FIFO control*(write only) |
| x 0 1 1 | Line control |
| x 1 0 0 | MODEM control |
| x 1 0 1 | Line status |
| x 1 1 0 | MODEM status |
| x 1 1 1 | Scratch |
| 1 0 0 0 | Divisor latch (LSB) |
| 1 0 0 1 | Divisor latch (MSB) |
+---------------+------------------------------+
Figure 2. Internal register map for 16450/16550 ACE.
DLAB is accessed through the Line Control
Register.
*with optional 16550.

FUNCTIONAL DESCRIPTION
INTERRUPT ENABLE REGISTER
+-------+
D7 | 0 |
+-------+
D6 | 0 |
+-------+
D5 | 0 |
+-------+
D4 | 0 |
+-------+
D3 | EDSSI |----- MODEM status
+-------+
D2 | ELSI |----- Receiver line status
+-------+
D1 | ETBEI |----- Transmitter holding register empty
+-------+
D0 | ERBFI |----- Received data available
+-------+
EDSSI - MODEM Status Interrupt:
When set (logic 1), enables interrupts on clear
to send, data set ready, ring indicator, and
data carrier detect.
ELSI - Receiver Line Status Interrupt:
When set (logic 1), enables interrupts on
overrun, parity, framing errors, and break
indication.
ETBEI - Transmitter Holding Register Empty Interrupt:
When set (logic 1), enables interrupts on
transmitter register empty.
ERBFI - Received Data Available Interrupt:
When set (logic 1), enables interrupts on
received data available or the receiver FIFO
trigger level*.
*with optional 16550.

FUNCTION
AL DESCRIPTION
INTERRUPT IDENTIFICATION REGISTER
+------+
D7 | FFE |--+
+------+ +-- FIFO enable *
D6 | FFE |--+
+------+
D5 | 0 |
+------+
D4 | 0 |
+------+
D3 | IID2 |--+
+------+ |
D2 | IID1 | +-- Interrupt identification
+------+ |
D1 | IID0 |--+
+------+
D0 | IP |----- Interrupt pending
+------+
FFE - FIFO Enable:*
When logic 1, indicates FIFO mode enabled.
IIDx - Interrupt Identification:
Indicates highest priority interrupt pending if
any. See IP and figure 3. NOTE: IID2 is
always a logic 0 in the 16450 and in the 16550
character mode.
IP - Interrupt Pending:
When logic 0, indicates that an interrupt is
pending and the contents of the interrupt
identification register may be used to determine
the interrupt source. See IIDx and figure 3.
*with optional 16550.

FUNCTIONAL DESCRIPTION
+--------------------+----------+----------------------+
| IID2 IID1 IID0 IP | Priority | Interrupt Type |
+--------------------+----------+----------------------+
| x x x 1 | N/A | None |
| 0 1 1 0 | Highest | Receiver Line Status |
| 0 1 0 0 | Second | Received Data Ready |
| 1 1 0 0 | Second | Character Timeout |
| | | (FIFO mode only)*|
| 0 0 1 0 | Third | Transmitter Holding |
| | | Register Empty |
| 0 0 0 0 | Fourth | MODEM Status |
+--------------------+----------+----------------------+
Figure 3. Interrupt Identification bit definitions.
Receiver Line Status:
Indicates overrun, parity, framing errors or
break interrupts. The interrupt is cleared by
reading the line status register.
Received Data Ready:
Indicates receive data available. The interrupt
is cleared by reading the receive buffer.
FIFO mode:*
Indicates the receiver FIFO trigger level has
been reached. The interrupt is reset when the
FIFO drops below the the trigger level.
Character Timeout: (FIFO mode only)*
Indicates no characters have been removed from
or input to the receiver FIFO for the last four
character times and there is at least one
character in the receiver FIFO. The interrupt
is cleared by reading the receiver FIFO.
Transmitter Holding Register Empty:
Indicates the transmitter holding register is
empty. The interrupt is cleared by reading the
interrupt identification register or writing to
the transmitter holding register.
MODEM Status:
Indicates clear to send, data set ready, ring
indicator, or data carrier detect have changed
state. The interrupt is cleared by reading the
MODEM status register.
*with optional 16550.

FUNCTION
AL DESCRIPTION
FIFO CONTROL REGISTER *
+------+
D7 | RXT1 |--+
+------+ +-- Receiver trigger *
D6 | RXT0 |--+
+------+
D5 | x |--+
+------+ +-- Reserved
D4 | x |--+
+------+
D3 | DMAM |----- DMA mode select *
+------+
D2 | XRST |----- Transmit FIFO reset *
+------+
D1 | RRST |----- Receive FIFO reset *
+------+
D0 | FE |----- FIFO enable *
+------+
RXTx - Receiver FIFO Trigger Level:*
Determines the trigger level for the FIFO
interrupt as given in figure 4 below.
+-----------+-----------------------+
| | RCVR FIFO |
| RXT1 RXT0 | Trigger level (bytes) |
+-----------+-----------------------+
| 0 0 | 1 |
| 0 1 | 4 |
| 1 0 | 8 |
| 1 1 | 14 |
+-----------+-----------------------+
Figure 4. FIFO trigger levels.
DMAM - DMA Mode Select:*
When set (logic 1), RxRDY and TxRDY change from
mode 0 to mode 1. (DMA mode is not supported by
the DS-202 / DS-302.)
XRST - Transmit FIFO Reset:*
When set (logic 1), all bytes in the transmitter
FIFO are cleared and the counter is reset. The
shift register is not cleared. XRST is self-
clearing.
*with optional 16550.

FUNCTIONAL DESCRIPTION
RRST - Receive FIFO Reset:*
When set (logic 1), all bytes in the receiver
FIFO are cleared and the counter is reset. The
shift register is not cleared. RRST is self-
clearing.
FE - FIFO Enable:*
When set (logic 1), enables transmitter and
receiver FIFOs. When cleared (logic 0), all
bytes in both FIFOs are cleared. This bit must
be set when other bits in the FIFO control
register are written to or the bits will be
ignored.
LINE CONTROL REGISTER
+------+
D7 | DLAB |----- Divisor latch access bit
+------+
D6 | BKCN |----- Break control
+------+
D5 | STKP |----- Stick parity
+------+
D4 | EPS |----- Even parity select
+------+
D3 | PEN |----- Parity enable
+------+
D2 | STB |----- Number of stop bits
+------+
D1 | WLS1 |--+
+------+ +-- Word length select
D0 | WLS0 |--+
+------+
DLAB - Divisor Latch Access Bit:
DLAB must be set to logic 1 to access the baud
rate divisor latches. DLAB must be set to logic
0 to access the receiver buffer, transmitting
holding register and interrupt enable register.
BKCN - Break Control:
When set (logic 1), the serial output (SOUT) is
forced to the spacing state (logic 0).
*with optional 16550.

FUNCTIONAL DESCRIPTION
STKP - Stick Parity:
Forces parity to logic 1 or logic 0 if parity is
enabled. See EPS, PEN, and figure 5.
EPS - Even Parity Select:
Selects even or odd parity if parity is enabled.
See STKP, PEN, and figure 5.
PEN - Parity Enable:
Enables parity generation on transmission and
verification on reception. See EPS, STKP, and
figure 5.
+--------------+---------+
| STKP EPS PEN | Parity |
+--------------+---------+
| x x 0 | None |
| 0 0 1 | Odd |
| 0 1 1 | Even |
| 1 0 1 | Logic 1 |
| 1 1 1 | Logic 0 |
+--------------+---------+
Figure 5. 16450/16550 parity selections.
STB - Number of Stop Bits:
Defines the number of stop bits per character.
See WLSx and figure 6.
WLSx - Word Length Select:
Defines the number of data bits per character.
See STB and figure 6.
+---------------+-------------+-----------+
| STB WLS1 WLS0 | Word length | Stop bits |
+---------------+-------------+-----------+
| 0 0 0 | 5 bits | 1 |
| 0 0 1 | 6 bits | 1 |
| 0 1 0 | 7 bits | 1 |
| 0 1 1 | 8 bits | 1 |
| 1 0 0 | 5 bits | 1½ |
| 1 0 1 | 6 bits | 2 |
| 1 1 0 | 7 bits | 2 |
| 1 1 1 | 8 bits | 2 |
+---------------+-------------+-----------+
Figure 6. Word length and stop bit selections.

FUNCTIONAL DESCRIPTION
MODEM CONTROL REGISTER
+------+
D7 | 0 |
+------+
D6 | 0 |
+------+
D5 | 0 |
+------+
D4 | LOOP |----- Loopback enable
+------+
D3 | OUT2 |----- Output 2
+------+
D2 | OUT1 |----- Output 1
+------+
D1 | RTS |----- Request to send
+------+
D0 | DTR |----- Data terminal ready
+------+
LOOP - Loopback Enable:
When set (logic 1), the transmitter shift
register is internally connected to the receiver
shift register, the MODEM control inputs are
internally connected to the MODEM control
outputs, and the outputs are forced to their
inactive state. Transmit and receive interrupts
operate normally but MODEM control interrupts
are now controlled through the MODEM control
register.
Bits OUT2, OUT1, RTS, and DTR perform identical
functions on their respective outputs. When these
bits are set (logic 1) in the register, the
associated output is forced to a logic 0. When
cleared (logic 0), the output is forced to a logic1.
OUT2 - Output 2:
Controls the OUT2 output as described above.
Used for interrupt enable, see section VI.
OUT1 - Output 1:
Controls the OUT1 output as described above.
OUT1 is unused on the DS-202 / DS-302.
RTS - Request To Send:
Controls the RTS output as described above.
Used for output driver control, see section VII.
DTR - Data Terminal Ready:
Controls the DTR output as described above.
Used for output driver control, see section VII.

FUNCTIONAL DESCRIPTION
LINE STATUS REGISTER
+------+
D7 | FFRX |----- Error in FIFO RCVR (FIFO only)*
+------+
D6 | TEMT |----- Transmitter empty
+------+
D5 | THRE |----- Transmitter holding register empty
+------+
D4 | BI |----- Break interrupt
+------+
D3 | FE |----- Framing error
+------+
D2 | PE |----- Parity error
+------+
D1 | OE |----- Overrun error
+------+
D0 | DR |----- Data ready
+------+
FFRX - FIFO Receiver Error:*
Always logic 0 in the 16450 and in the 16550
character mode.
FIFO mode:*
Indicates one or more parity errors, framing
errors, or break indications in the receiver
FIFO. FFRX is reset by reading the line status
register.
TEMT - Transmitter Empty:
Indicates the transmitter holding register (or
FIFO) and the transmitter shift register are
empty and are ready to receive new data. TEMT
is reset by writing a character to the
transmitter holding register.
THRE - Transmitter Holding Register Empty:
Indicates the transmitter holding register (or
FIFO) is empty and it is ready to accept new
data. THRE is reset by writing data to the
transmitter holding register (or FIFO).
*with optional 16550.

FUNCTIONAL DESCRIPTION
Bits BI, FE, PE, and OE are the sources of
receiver line status interrupts. These bits
are reset by reading the line status register.
In FIFO mode*, these bits are associated with a
specific character in the FIFO and the
exception is revealed only when that character
reaches the top of the FIFO.
BI - Break Interrupt:
Indicates the receive data input has been in the
spacing state (logic 0) for longer than one full
word transmission time.
FIFO mode:*
Only one zero character is loaded into the FIFO
and transfers are disabled until SIN goes to the
mark state (logic 1) and a valid start bit is
received.
FE - Framing Error:
Indicates the received character had an invalid
stop bit. The stop bit following the last data
or parity bit was a 0 bit (spacing level).
PE - Parity Error:
Indicates that the received data does not have
the correct parity.
OE - Overrun Error:
Indicates the receive buffer was not read before
the next character was received and the
character is destroyed.
FIFO mode:*
Indicates the FIFO is full and another character
has been shifted in. The character in the shift
register is destroyed but is not transferred to
the FIFO.
DR - Data ready:
Indicates data is present in the receive buffer
or FIFO. DR is reset by reading the receive
buffer register or receiver FIFO.
*with optional 16550.

FUNCTIONAL DESCRIPTION
MODEM STATUS REGISTER
+------+
D7 | DCD |----- Data carrier detect
+------+
D6 | RI |----- Ring indicator
+------+
D5 | DSR |----- Data set ready
+------+
D4 | CTS |----- Clear to send
+------+
D3 | DDCD |----- Delta data carrier detect
+------+
D2 | TERI |----- Trailing edge ring indicator
+------+
D1 | DDSR |----- Delta data set ready
+------+
D0 | DCTS |----- Delta clear to send
+------+
DCD - Data Carrier Detect:
Complement of the DCD input.
RI - Ring Indicator:
Complement of the RI input.
DSR - Data Set Ready:
Complement of the DSR input.
CTS - Clear To Send:
Complement of the CTS input.
Bits DDCD, TERI, DDSR, and DCTS are the sources of
MODEM status interrupts. These bits are reset when
the MODEM status register is read.
DDCD - Delta Data Carrier Detect:
Indicates the Data Carrier Detect (DCD) input
has changed state.
TERI - Trailing Edge Ring Indicator:
Indicates the Ring Indicator (RI) input has
changed from a low to a high state.
DDSR - Delta Data Set Ready:
Indicates the Data Set Ready (DSR) input has
changed state.
DCTS - Delta Clear To Send:
Indicates the Clear to Send (CTS) input has
changed state.

FUNCTIONAL DESCRIPTION
SCRATCHPAD REGISTER
This register is not used by the 16450/16550. It
may be used by the programmer for data storage.
FIFO INTERRUPT MODE OPERATION *
1. The receive data interrupt is issued when the FIFO
reaches the trigger level. The interrupt is
cleared as soon as the FIFO falls below the
trigger level.
2. The interrupt identification register's receive
data available indicator is set and cleared along
with the receive data interrupt above.
3. The data ready indicator is set as soon as a
character is transferred into the receiver FIFO
and is cleared when the FIFO is empty.
IV. BAUD RATE SELECTION
The 16450/16550 ACE determines the baud rate of
the serial output using a combination of the input
clock frequency and the value written to the baud rate
divisor latches. Standard PC, PC/XT, PC/AT, and PS/2
serial interfaces use an input clock of 1.8432 MHz. To
increase versatility, the DS-202 / DS-302 uses an
18.432 MHz crystal and a frequency divider circuit to
produce the standard clock frequency.
Jumper block J1 is used to set the frequency input
to the ACE. The jumper may be connected to divide the
18.432 MHz clock input by 1, 2, 5, or 10. For
compatibility as stated above, J1 should be configured
to divide by 10 as shown in figure 7(d). A table of
baud rates available using the 1.8432 MHz input is
given in figure 7.
*with optional 16550.

BAUD
RATE SELECTION
J1 J1
+---------+ +---------+
4| _ +_ _ |6 4| _--_ _ |6
1| _ +_ _ |3 1| _ _--_ |3
+---------+ +---------+
(a) ÷1 input clock (b) ÷2 input clock
J1 J1
+---------+ +---------+
4| _ _--_ |6 1| _--_ +_ |4
1| _--_ _ |3 2| _--_ +_ |5
+---------+ +---------+
(c) ÷5 input clock (d) ÷10 input clock
Figure 7. Input clock frequency options. For
compatibility, the jumper should be set
to ÷10 ( 18.432 MHz ÷ 10 = 1.8432 MHz ).
+-----------+-------------+-----------------------+
| Desired | Divisor | Error Between Desired |
| Baud Rate | Latch Value | and Actual Value (%) |
+-----------+-------------+-----------------------+
| 50 | 2304 | - |
| 75 | 1536 | - |
| 110 | 1047 | 0.026 |
| 150 | 768 | - |
| 300 | 384 | - |
| 600 | 192 | - |
| 1200 | 96 | - |
| 1800 | 64 | - |
| 2000 | 58 | 0.69 |
| 2400 | 48 | - |
| 3600 | 32 | - |
| 4800 | 24 | - |
| 7200 | 16 | - |
| 9600 | 12 | - |
| 19200 | 6 | - |
| 38400 | 3 | - |
| 56000 | 2 | 2.86 |
+-----------+-------------+-----------------------+
Figure 8. Divisor latch
settings for common baud
rates using a 1.8432 MHz
input clock. The jumper
must be set to the divide by
10 configuration (figure
7(d)).

BAUD
RATE SELECTION
V. ADDRESSING
Each channel of the DS-202 / DS-302 uses eight
consecutive I/O address locations in the range 0 to
07FF Hex. The base address of channel 1 is selected
using dip switch SW1 while the base address of channel
2 is selected using SW2. Switch positions 1 - 8
control the selection of address lines A9 through A3
respectively. A switch set to the "ON" position
requires the corresponding address bit to be "0" for
channel selection while a switch set to the "OFF"
position requires the address bit to be "1". Address
lines A10 - A15 must be "0" for port selection. Some
address selection examples are given in figure 10.
Jumper J4 is used to independently enable or
disable the communication channels. Connecting J4 pins
1 and 3 enables channel 1 while connecting J4 pins 2
and 4 enables channel 2. A channel may be disabled by
removing the corresponding jumper from J4. The layout
of jumper J4 is shown in figure 11.
SW1
+----------------------------+
| 1 2 3 4 5 6 7 8 |
|ON +-++-++-++-++-++-++-++-+ |
| |_|| || || || || || || | |
| | ||_||_||_||_||_||_||_| |
| +-++-++-++-++-++-++-++-+ |
+----------------------------+
(a) Address selection switch
for channel 1. Shown is setting
for base address 03F8H (COM1).
SW2
+----------------------------+
| 1 2 3 4 5 6 7 8 |
|ON +-++-++-++-++-++-++-++-+ |
| |_|| ||_|| || || || || | |
| | ||_|| ||_||_||_||_||_| |
| +-++-++-++-++-++-++-++-+ |
+----------------------------+
(b) Address selection switch
for channel 2. Shown is setting
for base address 02F8H (COM2).
Figure 9. Address selection switches.

ADDRESSING
1 2 3 4 5 6 7 8
ON +-++-++-+ +-++-++-++-+ +-+
|_|| || | | || || || | | |
| ||_||_| |_||_||_||_| |_|
+-++-++-+ +-++-++-++-+ +-+
0 2 1 8 4 2 1 8
BASE ADDRESS 3 F 8 = 03F8H
1 2 3 4 5 6 7 8
ON +-++-++-+ +-++-++-++-+ +-+
|_|| ||_| | || || || | | |
| ||_|| | |_||_||_||_| |_|
+-++-++-+ +-++-++-++-+ +-+
0 2 0 8 4 2 1 8
BASE ADDRESS 2 F 8 = 02F8H
1 2 3 4 5 6 7 8
ON +-++-++-+ +-++-++-++-+ +-+
|_|| || | | || || ||_| | |
| ||_||_| |_||_||_|| | |_|
+-++-++-+ +-++-++-++-+ +-+
0 2 1 8 4 2 0 8
BASE ADDRESS 3 E 8 = 03E8H
1 2 3 4 5 6 7 8
ON +-++-++-+ +-++-++-++-+ +-+
|_|| ||_| | || || ||_| |_|
| ||_|| | |_||_||_|| | | |
+-++-++-+ +-++-++-++-+ +-+
0 2 0 8 4 2 0 0
BASE ADDRESS 2 E 0 = 02E0H
Figure 10. Address selection examples.
J4
+------+
3 | _ _ | 4
1 | _ _ | 2
+------+
enable channel 1 --+ +-- enable channel 2
Figure 11. Channel enable / disable jumper.
Connecting pins 1 - 3 enables channel 1.
Connecting pins 2 - 4 enables channel 2.