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Date: 20.04.04

Page 21 of 30

Title:

Data Sheet GC-IP200

Name of Document:

43500-DB-2-1-E-IP200.pdf

8

Error Processing

The IP200 has 6 sources for generating the global error signal. Each source can be activated by the

corresponding bit in the error mask register. With the LatchErr bit being activated, the individual error

signals are stored until the next chip reset or until the next SPI ResetCount command (command 0x01)

occurs, respectively. The logic OR function of the masked and stored error signals appears as a low active

signal on pin NERR. With the HoldErr bit being active, the A, B and OREF outputs freeze in the current state

on error case. The NERR and NRES pins can be shorted in order to re-synchronise the IC in the event of an

error. The error signal is active for 8 system clocks in this case.

Error Mask Register

Bit

Description (if bit is set)

GCOMP

Gain controller reaches his limit

OCOMP

Offset controller reaches his limit

BQLOW

Amplitude Error: the resulting Sine-Cosine-Vector is to small

ADUOVL

One or both ADC-Converter are clipping

FAST1

Signal frequency to high, no signal direction recognition possible (SPEED=1),

Signal frequency to fast for proper generating A/B/OREF - Signals (SPEED=0)

FAST2

Signal frequency to fast for proper generating the A/B/OREF - Signals (depends

upon IT(2:0)

, refer also to table “Clock Frequency Examples” in chapter 4.4)

HoldErr

The A/B/OREF - Signals freeze in error case

LatchErr

The masked error signal is stored until next SPI-reset-command or a global reset

occurs, respectively



For square wave operation (A/B-Signals) it is recommended to set the error mask register to 0x3F or 0xFF

respectively, in counter mode use the error mask register loaded with 0xDF and set the SPEED bit in the

CFG0

register.

The status register STAT contains all error bits. The MVAL and CNT register contain logic combinations

of counter relevant error bits:

SENSERR = ADUOVL or BQLOW or OCOMP or GCOMP

AMPERR = ADUOVL or BQLOW

Sensor breakage error:

Partial or complete tearing off of the connected sensor is detected in the IP200 at the time of occurrence.

Thereafter, the automatic gain-offset-controller tries to compensate this error which, due to the large

operating range of the gain-offset-controller, can lead to a situation where the cause of this error seems to

have been eliminated.