DS2182A

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PIN DESCRIPTION Table 2

PIN

SYMBOL

TYPE

DESCRIPTION

1

INT

O

Receive Alarm Interrupt. Flags host controller during alarm conditions.

Active low; open drain output.

2

SDI

I

Serial Data In. Data for onboard registers. Sampled on rising edge of SCLK.

3

SDO

O

Serial Data Out. Control and status information from onboard registers.

Updated on falling edge of SCLK; tri-stated during serial port write or

when CS is high.

4

CS

I

Chip Select. Must be low to read or write the serial port.

5

SCLK

I

Serial Data Clock. Used to read or write the serial port registers.

POWER AND TEST PIN DESCRIPTION Table 3

PIN

SYMBOL

TYPE

DESCRIPTION

14

-

Signal Ground. 0.0 volts.

20

TEST

I

28

-

Positive Supply. 5.0 volts.

REGISTER SUMMARY Table 4

REGISTER

ADDRESS

DESCRIPTION/FUNCTION

BVCR2

0000

Bipolar Violation Count Register 2. LSW of a 16-bit presettable counter that

records individual bipolar violations.

BVCR1

0001

Bipolar Violation Count Register 1. MSW of a 16-bit presettable counter that

records individual bipolar violations.

CRCCR

0010

CRC Error Count Register. 8-bit presettable counter that records CRC6 errored

words in the 193E frame mode.

OOFCR

0011

OOF Count Register. 8-bit presettable counter that records OOF events. OOF

events are defined by RCR1.5 and RCR1.6.

FECR

0100

Frame Error Count Register. 8-bit presettable counter that records individual

bit errors in the framing pattern.

RSR1

0101

Receive Status Register 1. Reports alarm conditions.

RIMR1

0110

Receive Interrupt Mask Register 1. Allows masking of individual alarm-

generated interrupts from RSR1.

RSR2

0111

Receive Status Register 2. Reports alarm conditions.

RIMR2

1000

Receive Interrupt Mask Register 2. Allows masking of individual alarm-

generated interrupts from RSR2.

RCR1

1001

Receive Control Register 1. Programs device operating characteristics.

RCR2

1010

Receive Control Register 2. Programs device operating characteristics.

SERIAL PORT INTERFACE

The port pins of the DS2182A serve as a microprocessor/ microcontroller-compatible serial port. Eleven

on-board registers allow the user to update operational characteristics and monitor device status via a host

controller, minimizing hardware interfaces. The port on the DS2182A can be read from or written to at

any time. Serial port reads and writes are independent of T1 line timing signals RCLK, RPOS, and

RNEG. However, RCLK is needed in order to clear RSR1 and RSR2 after reads.

ADDRESS/COMMAND

Reading or writing the control, configuration or status registers requires writing one address/command

byte prior to transferring register data. The first bit written (LSB) of the address/command word specifies