PCD6003 Datasheet, PDF (43/96 Pages) NXP Semiconductors – Digital telephone answering machine chip

Philips Semiconductors
Digital telephone answering machine chip
Product specification
PCD6003
Table 43 Description of MSTAT bits
BIT
SYMBOL
DESCRIPTION
7
MPOL MIN polarity switch. If MPOL = 1, the value of the MIN pin is inverted before being
applied to the MSK block.
5
MRF Modem receiver full flag. This bit is set when MBUF holds a newly received byte. MRF
is reset if the receiver is disabled (MREN = 0) or by reading MBUF. This bit is read-only.
Writing to it will have no effect.
4
MRE Modem Receiver Error flag. Indicates the reception of a non-Manchester bit. This bit is
set by hardware and is reset by reading MBUF, by disabling the receiver (MREN = 0) or
by resetting MRI. This bit is read-only. Writing to it will have no effect.
3
MRP Modem Receiver Preamble flag. This bit is set by hardware when the modem
recognized the programmed preamble pattern (AAAH, MPR3 to MPR0) after locking the
receiver clock (MRL = 1). MRP is reset by hardware if the receiver is disabled
(MREN = 0) or if non-Manchester data is received (MRE = 1). This bit is read-only.
Writing to it will have no effect.
2
MRL
Modem Receiver Clock Locked flag. This bit is set when the clock of the receiver is
locked, i.e. when the receiver has detected Manchester data but has not found the
preamble pattern yet. MRL is reset when the receiver detects a non-Manchester bit or
when the receiver is disabled. This bit is read-only. Writing to it will have no effect.
1
MTI
Modem Transmit Interrupt flag. Indicates MBUF is empty to accept a new byte for
transmission. This bit is reset by writing to MBUF or by writing a 0 to it. Writing a 1 to
MTI will set the bit. This allows to generate a hardware interrupt by software.
0
MRI
Modem Receive Interrupt flag. Indicates:
Modem Receiver Full (MRF = 1) or
Modem Receiver Error (MRE = 1) or
Modem Receiver Preamble (MRP = 1) or
Modem Receiver Clock Locked (MRL = 1)
This bit is reset by reading MBUF or by writing a logic 0 to MRI. A reset of MRI will also
reset MRE. Writing a logic 1 to MRI will have no effect.
10.12.1.3 MSK Modem Data Buffer (MBUF)
Table 44 MSK Modem Data Buffer (SFR address C9H)
7
6
5
4
3
2
1
0
D7
D6
D5
D4
D3
D2
D1
D0
Table 45 Description of MBUF bits
BIT
7 to 0
SYMBOL
D7 to D0
DESCRIPTION
Writing to MBUF will load the data in the transmit buffer and automatically start a
transmission at MOUT if the transmitter is enabled (MTEN = 1). A new byte can be
loaded after MTI is set. If a new byte is loaded before the setting of MTI then the
previous byte will be lost. After data has been received at MIN, indicated by MRI, the
received byte can be read from MBUF.
2001 Apr 17
43