MT8880CE Zarlink, MT8880CE Datasheet - Page 17

• Manufacturer Part Number: MT8880CE
• Description: DTMF TXRX 3.58MHz CMOS 5V 20-Pin PDIP Tube
• Manufacturer: Zarlink

Specifications of MT8880CE

• Package: 20PDIP
• Operating Frequency: 3.58 MHz
• Typical Supply Current: 11 mA
• Typical Operating Supply Voltage: 5 V
• Minimum Operating Supply Voltage: 4.75 V
• Maximum Operating Supply Voltage: 5.25 V

EXAMPLE 1: A software reset must be included at the beginning of all programs to initialize the control registers
after power up. The initialization procedure should be implemented 100ms after power up.
Description
1) Read Status Register
2) Write to Control Register
3) Write to Control Register
4) Write to Control Register
5) Write to Control Register
6) Read Status Register
EXAMPLE 2: Transmit DTMF tones of 50 ms burst/50 ms pause and Receive DTMF Tones
Description
1) Write to Control Register A
2) Write to Control Register B
3) Write to Transmit Data Register
--------------------------------------wait for an interrupt or poll Status Register ----------------------------------------------
4) Read the Status Register
NOTE: IN THE TX BURST MODE, STATUS REGISTER BIT 1 WILL NOT BE SET UNTIL 100 ms (
WRITTEN TO THE TX DATA REGISTER. IN EXTENDED BURST MODE THIS TIME WILL BE DOUBLED TO 200 ms (
-if bit 1 is set, the Tx is ready for the next tone, in which case...
Write to Transmit Register
(send a digit 5)
-if bit 2 is set, a DTMF tone has been received, in which case....
Read the Receive Data Register
-if both bits are set...
Read the Receive Data Register
Write to Transmit Data Register
(tone out, DTMF, IRQ, Select Control Register B)
(burst mode)
(send a digit 7)
Figure 16 - Application Hints
Zarlink Semiconductor Inc.
MT8880C
CS
CS
17
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Control
RS0
RS0
1
1
1
1
1
1
1
1
0
1
0
0
0
0
R/W
R/W
1
0
0
0
0
1
0
0
0
1
0
1
1
0
b3
b3
X
0
0
1
0
X
1
0
0
X
0
X
X
0
±
2 ms) AFTER THE DATA IS
Data
b2
b2
X
0
0
0
0
X
1
0
1
X
1
X
X
1
b1
b1
X
0
0
0
0
X
0
0
1
X
0
X
X
0
Data Sheet
±
4 ms)
b0
b0
X
0
0
0
0
X
1
0
1
X
1
X
X
1
.