SLRC400 Datasheet, PDF (22/130 Pages) NXP Semiconductors – I·CODE Reader IC

Philips Semiconductors
I•CODE Reader IC
Product Specification Rev. 2.0 November 2001
SL RC400
5.2.1.4 PrimaryStatus Register
Status flags of the receiver, transmitter and the FIFO buffer.
Name: PrimaryStatus
Address: 0x03
7
0
Access
r
Rights
6
5
4
ModemState
r
r
r
Reset value: 00000001, 0x01
3
2
1
0
IRq
Err
HiAlert LoAlert
r
r
r
r
Description of the bits
Bit
Symbol
Function
7
0
Reserved for future use.
6-4 ModemState ModemState shows the state of the transmitter and receiver state machines.
State
000
Name of State
Idle
001 TxSOF
Description
Neither the transmitter nor the receiver is in operation,
since none of them is started or
since none of them has got input data.
Transmitting the ‘Start Of Frame’ Pattern.
010 TxData
011 TxEOF
Transmitting data from the FIFO buffer (or redundancy
check bits).
Transmitting the ‘End Of Frame’ Pattern.
100 GoToRx1
GoToRx2
101 PrepareRx
110 AwaitingRx
Mean-State passed, when receiver starts.
Mean-State passed, when receiver finishes.
Waiting until the time period selected in the RxWait
Register has expired.
Receiver activated; Awaiting an input signal at pin Rx.
111 Receiving
Receiving data.
3
IRq
This bit shows, if any interrupt source requests attention (with respect to the
setting of the interrupt enable flags in the InterruptEn Register).
2
Err
This bit is set to 1, if any error flag in the ErrorFlag Register is set.
1
HiAlert
Is set to 1, when the number of bytes stored in the FIFO buffer fulfil the following
equation: HiAlert = (64 − FIFOLength) ≤ WaterLevel
Example:
FIFOLength=60, WaterLevel=4 ⇒ HiAlert =1
FIFOLength=59, WaterLevel=4 ⇒ HiAlert =0
0
LoAlert
Is set to 1, when the number of bytes stored in the FIFO buffer fulfil the following
equation: LoAlert = FIFOLength ≤ WaterLevel
Example:
FIFOLength=4, WaterLevel=4
FIFOLength=5, WaterLevel=4
⇒ LoAlert =1
⇒ LoAlert =0
22
Preliminary