AK2346A Datasheet, PDF (30/37 Pages) Asahi Kasei Microsystems – Two-way Radio Audio Processor

ASAHI KASEI
[AK2346A]
17. MSK Modem Description
1) MSK Modulator control flow
MSK data transmitter, Modulator interfaces with MSKCLK, MSKDATA and MOD pins and also
TXRX, TXSW2, TXSW1, TXSW0, MSKSW1 and MSKSW0 register as below.
TXRX=0
MSKSW[1:0]=0/1
TXSW[2:0]=1/0/1
: MSK data transmit start
MSK data are transmitted
synchronized to MSKCLK clock
N
Required bit
Y
number completed
Y
MSKSW1=1
: MSK data transmitting
: MSK data transmit compete
Waiting 2ms or more
MSKSW1=0
: Switching to audio signal
(1) Setting TXRX=0, MSKSW1=0, MSKSW0=1, TXSW2=1 and TXSW1=0, MSK data transmit is
provided.
(2) A 1200/2400Hz clock is put out from MSKCLK pin. Synchronizing with the rising edge of
MSKCLK,
AK2346A reads the MSK transmit data from MSKDATA pin and puts out them to MOD pin.
(3) After transmitting the necessary bit number, please set MSKSW1=1
(4) Afterwards, before switching to audio signal mode, please wait for at least 2ms after setting
MSKSW1=1 to complete sending the MSK data final data bit transmit. Then set
TXSW[2:0]=”1/1/0”.
MS1289-E-02
- 30 -
2012/06