M-8880 CLARE [Clare, Inc.], M-8880 Datasheet - Page 6

• Manufacturer Part Number: M-8880
• Description: M-8880 DTMF Transceiver
• Manufacturer: CLARE [Clare, Inc.]

registers on powerup; however, as a precautionary measure the
initialization software should include a routine to clear the regis-
ters. Refer to Tables 3 and 4 for details on the control registers.
The IRQ/CP pin can be programmed to provide an interrupt re-
quest signal on validation of DTMF signals, or when the trans-
mitter is ready for more data (burst mode only). The IRQ/CP pin
is configured as an open-drain output device and as such re-
quires a pullup resistor (see Figure 10).
Ordering Information
M-888001P
M-8880-01SM
M-8880-01T
40-406-00012, Rev. G
RS0
0
0
1
1
Table 6 Internal Register Functions
R/W
0
1
0
1
20-pin plastic DIP
20-pin plastic SOIC
20-pin plastic SOIC,Tape and Reel
Read from status register
Write to control register
Figure 10 Application Circuit (Single-Ended Input)
Read from receiver
Write to transmitter
Function
Page 6
M-8880
RSEL
C/R
b3
b3
Table 8 CRB Bit Positions
Table 7 CRA Bit Postions
Figure 9 Equations
IRQ
S/D
b2
b2
CP/DTMF
TEST
b1
b1
www.clare.com
BURST
TOUT
b0
b0