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MC145572
3–3
MOTOROLA
Table 3–3. Digital Data Interface Pins (See Section 3.3.4)
Pin Name
Pin No.
MCU/
SCP
Mode
MCU/PCP
Mode
GCI
Mode
TQFP
PLCC
Pin Description
SCPEN
CS
IN1
4
21
In serial port, MCU mode, SCPEN is the active low SCP enable input.
In parallel port, MCU mode, CS is the active low chip select.
In full GCI mode, defined when MCU/GCI = 0, this input is IN1.
SCPCLK
R/W
IN2
3
20
In serial port, MCU mode, SCPCLK is the serial control port clock input.
In parallel port, MCU mode, R/W is the read versus write indication to the
parallel port.
In full GCI mode, defined when MCU/GCI = 0, this input is IN2.
SCPRx
D0
OUT1
1
18
In serial port, MCU mode, SCPRx is the serial control port data input.
In parallel port, MCU mode, D0 is the LSB of the parallel data bus.
In full GCI mode, defined by MCU/GCI = 0, OUT1 is an output reflecting the
state of bit 5 as set in BR7.
SCPTx
D1
OUT2
2
19
In serial port, MCU mode, SCPTx is the serial control port data output.
In parallel port, MCU mode, this is signal D1 of the parallel data bus.
In full GCI mode, defined by MCU/GCI = 0, OUT2 is an output reflecting the
state of bit 6 as set in BR7
IRQ
IRQ
—
44
17
Open–drain active low output for microcontroller interrupt.
4.096
CLKOUT
D2
4.096
CLKOUT
17
34
4.096 MHz clock out.
In parallel port, MCU mode, this is signal D2 of the parallel data bus.
15.36
CLKOUT
D3
15.36
CLKOUT
18
35
15.36 MHz clock out. Not synchronized to recovered clock in the NT mode.
In parallel port, MCU mode, this is signal D3 of the parallel data bus.
BUFXTAL
D4
BUFXTAL
21
38
This is a square wave output from the 20.48 MHz oscillator and it is not
synchronized to the recovered clock in the NT mode.
In parallel port, MCU mode, this is signal D4 of the parallel data bus.
EYEDATA
DCHCLK
D5
S2
22
39
In serial port, MCU mode, this pin may carry either EYEDATA or DCHCLK.
In parallel port, MCU mode, this is signal D5 of the parallel data bus.
In full GCI mode, this pin is the S2 input.
TxBCLK
DCHin
D6
FREFout
23
40
In serial port, MCU mode, this pin may carry either TxBCLK or DCHin.
TxBCLK is an 80 kHz clock output, aligned and synchronized to the
transmitted baud.
DCHin is the D channel port serial data input.
In parallel port, MCU mode, this is signal D6 of the parallel data bus.
In full GCI mode, operating as a GCI slave, this pin provides 2.048 MHz or
512 kHz synchronized clock output.
RxBCLK
DCHout
D7
CLKSEL
24
41
In serial port, MCU mode, this pin may carry either RxBCLK or DCHout.
RxBCLK is an 80 kHz clock output, aligned and synchronized to the received
baud.
DCHout is the D channel port serial data output.
In parallel port, MCU mode, D7 is the MSB of the parallel data bus.
In full GCI mode, operating as a GCI master, CLKSEL selects between
512 kHz and 2.048 MHz for DCL. CLKSEL = 1 selects 2.048 MHz.
SYSCLK
20.48 MHz
SFAR
TSEN
SYSCLK
20.48 MHz
SFAR
TSEN
S1
8
25
In either MCU mode, this pin may carry either SYSCLK, 20.48 MHz, SFAR, or
TSEN outputs.
SYSCLK is a 10.24 MHz clock for sampling EYEDATA.
SFAR is the receive data superframe alignment output in the NT and LT
modes.
TSEN is an active low open–drain buffer enable output, used for enabling a
bus driver to buffer MCU data out from the MC145572, onto a PCM highway.
TSEN is active only when Dout is active.
In full GCI mode, this pin is the S1 input.
TxSFS
SFAX
TxSFS
SFAX
S0
9
26
In either MCU mode, this pin may carry either TxSFS output, or SFAX
input/output.
When this pin is unused, connect a 100 k
resistor to VSS in LT mode.
TxSFS is provided for compatibility to the MC145472, which provides an
absolute transmit superframe reference.
SFAX is the transmit data superframe alignment input in the LT mode, or
superframe alignment output in the NT mode.
In LT mode, SFAX can also be an output.
In full GCI mode, this pin is the S0 input.