MT8888C/MT8888C-1
5.0 VDC
MMD6150 (or
equivalent)
TEST POINT
2.4 kΩ
5.0 VDC
3 kΩ
TEST POINT
130 pF
24 kΩ
MMD7000 (or
equivalent)
100 pF
Test load for D0-D3 pins
Test load for IRQ/CP pin
Figure 14 - Test Circuits
INITIALIZATION PROCEDURE
A software reset must be included at the beginning of all programs to initialize the control registers
power up.The initialization procedure should be implemented 100ms after power up.
Description:
Control
Data
RD
b3
b2
b1
RS0
WR
1) Read Status Register
1
1
0
X
X
X
2) Write to Control Register
1
0
1
0
0
0
3) Write to Control Register
1
0
1
0
0
0
4) Write to Control Register
1
0
1
1
0
0
5) Write to Control Register
1
0
1
0
0
0
6) Read Status Register
1
1
0
X
X
X
TYPICAL CONTROL SEQUENCE FOR BURST MODE APPLICATIONS
Transmit DTMF tones of 50 ms burst/50 ms pause and Receive DTMF Tones.
Sequence:
1)
2)
3)
4)
5)
RS0
Write to Control Register A
1
(tone out, DTMF, IRQ, Select Control Register B)
Write to Control Register B
1
(burst mode)
Write to Transmit Data Register
0
(send a digit 7)
Wait for an interrupt or poll Status Register
Read the Status Register
1
WR
0
0
0
RD
1
1
1
b3
1
0
0
b2
1
0
1
b1
0
0
1
b0
1
0
1
after
b0
X
0
0
0
0
X
1
0
X
X
X
X
-if bit 1 is set, the Tx is ready for the next tone, in which case...
Write to Transmit Register
0
0
(send a digit 5)
-if bit 2 is set, a DTMF tone has been received, in which case....
Read the Receive Data Register
0
1
-if both bits are set...
Read the Receive Data Register
Write to Transmit Data Register
1
0
1
0
1
0
X
X
X
X
0
0
1
0
0
1
X
0
X
1
X
0
X
1
NOTE: IN THE TX BURST MODE, STATUS REGISTER BIT 1 WILL NOT BE SET UNTIL 100 ms (±2 ms) AFTER THE DATA IS
WRITTEN TO THE TX DATA REGISTER. IN EXTENDED BURST MODE THIS TIME WILL BE DOUBLED TO 200 ms (± 4 ms)
.
Figure 15 - Application Notes
4-101
MITEL [ MITEL NETWORKS CORPORATION ]
