AK2346B Datasheet, PDF (23/31 Pages) Asahi Kasei Microsystems – Two-way Radio Audio Processor

ASAHI KASEI
[AK2346B]
15. MSK MODEM Description
1) MSK Modulator control flow
MSK data transmitter, Modulator interfaces with TCLK, TDATA and MOD pins and also TXRX,
TXSW2 and TXSW1 register as below.
TXRX=0
TXSW2=0
TXSW1=1
MSK data are transmitted
synchronized to TCLK clock
N
Required bit
Y
number completed
Y
TXSW2=1
Waiting 2ms or more
TXSW1=0
: MSK data transmit start
: MSK data transmitting
: MSK data transmit compete
: Switching to audio signal
(1) Setting TXRX=0, TXSW2=0 and TXSW1=1, MSK data transmit is provided.
(2) A 1200/2400Hz clock is put out from TCLK pin. Synchronizing with the rising edge of TCLK,
AK2346B reads the MSK transmit data from TDATA pin and puts out them to MOD pin.
(3) After transmitting the necessary bit number, please set TXSW2=1
(4) Afterwards, before switching to audio signal mode, please wait for at least 2ms after setting
TXSW2=1 to complete sending the MSK data final data bit transmit. Then set TXSW1=1.
MS1409-E-00
- 23 -
2012/05