DS2182A

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SERIAL PORT READ/WRITE Figure 3

NOTES:

1. SDI is sampled on rising edge of SCLK.

2. SDO is updated on falling edge of SCLK.

OPERATION OF THE COUNTERS

All four of the counters in the DS2182A can be preset by the user to establish an event count interrupt

threshold. The counters count up from the preset value until they reach saturation. At saturation, each

additional event occurrence sets the appropriate bit in RSR2 and generates an interrupt if enabled by

RIMR2.

The DS2182A contains an auto counter reset feature in the burst read mode. If RCR1.4 is set, then the

user can burst read the four counters (five registers), and all four counters will be automatically reset to 0

has the option of reading all of the registers or only the counters. If RCR1.4 is set, then any read of the

registers, burst mode or not, will clear the count in all four counters. If the user wishes to read the port

and not clear the counters, then RCR1.4 must be cleared first.

The counter registers can be read or written to at any time with the serial port, which operates totally

asynchronously with the monitoring of the T1 line. Reading a register will not affect the count as long as

RCR1.4 is cleared. The dual buffer architecture of the DS2182A insures that no error events will be

missed while the serial port is being accessed for reads.

BVCR1: BIPOLAR VIOLATION COUNT REGISTER 1;

BVCR2: BIPOLAR VIOLATION COUNTER REGISTER 2 Figure 4

MSB

LSB

BV7

BV6

BV5

BV4

BV3

BV2

BV1

BV0

SYMBOL

POSITION

NAME AND DESCRIPTION

BV7

BVCR.7

MSB of bipolar violation count

BV0

BVCR.0

LSB of bipolar violation count

Bipolar Violation Count Register 1 (BVCR1) is the most significant word and BVCR2 is the least

significant word of a presettable 16-bit counter that records individual bipolar violations. If the B8ZS

mode is enabled (RCR2.2 = 1), then B8ZS code words are not counted. The BVCR can also be

programmed to count excessive zeros by setting the RCR2.5 bit. In this mode, the BVCR will count