MLX90129_12 Datasheet, PDF (30/60 Pages) Melexis Microelectronic Systems – 13.56MHZ SENSOR TAG / DATALOGGER IC

MLX90129
13.56MHZ SENSOR TAG / DATALOGGER IC
RFID interrupt & status word (Devices address domain, address #01, read-only)
Bits Name
Description (if bit=1)
#01 – RFID interrupt & status word
15:13 _(reserved)
12 Irq_ExternalEvent
The pin AT has been disconnected from the GND.
11:8 _(reserved)
7 Irq_Sensor_Threshold The output data from the sensor has crossed the defined threshold
level or window
6 Irq_Timer_WakeUp
The count-down of the wake-up is over
5 Irq_DMA_ready
The DMA transaction has been completed (in the non-loop mode)
4 Irq_EEPROM_Full
The allocated memory for a datalogging with loop enable is full. The
datalogger starts to overwrite the first data.
3
(unused)
2 Transaction_Error_Flag One of the previously executed commands has failed (delay not
fulfilled, denied access, data not processed …). This bit is
automatically cleared after power-on or after read of the RFID interrupt
& status word.
1 Last_Transaction_Status This bit indicates whether the last request has been processed (‘0’) or
not (‘1’). In this latter case, the MLX90129 ignores any new request.
0 Core_Main_Status
The system is busy with an internal operation and the request from
RFID cannot be processed.
The following table summarizes the information about the interrupts which can be used with a RFID
communication. The RFID interrupt & status word in the Internal Device domain at the address 0x01 gives
the status of the interruptions. It is read only. It can be accessed with the command Read Internal Device.
For each bit of the RFID interrupt & status word, the condition to assert high or low the status flag is
described.
Interrupt description
Irq_ExternalEvent
IRQ enable conditions
Status flag is set to ‘1’ when
Reset condition
Set to ‘1’ the bits 9 and 11 of the register #12
Pin AT is not connected to GND
Pin AT is connected to GND
Irq_Sensor_Threshold
IRQ enable conditions
Status flag is set to ‘1’ when
Reset condition
Set to ‘1’ the bits 8,9,10 of the registers #15, #1B, #21
The last ADC output code crosses the defined threshold level or window
The chip is requested to read a new value of the sensor
Irq_Timer_WakeUp
IRQ enable conditions
Status flag is set to ‘1’ when
Reset condition
Set to ‘1’ the bit 0 of the register #10
The timer has completed its counting phase
The timer is requested to start a new counting phase (during the automatic
logging mode)
Irq_DMA_ready
IRQ enable conditions
Status flag is set to ‘1’ when
Reset condition
Set to ‘1’ the bit 2 of the register #09
The DMA unit has completed the last requested transaction
Read the RFID interrupt & status word
3901090129
Rev 009
Page 30 of 60
Data Sheet
Jun/12