Ssi Interface; Figure 4-6 Diagram Of Ssi Interface - Hytera MD78X Service Manual

Service Manual
The MICROWIRE interface can accommodate 4 external devices at most, generally transmitting
control and status messages of external devices, and reading data from ROM. Its maximum clock
frequency is a quarter of system clock frequency. In this case, MICROWIRE is used to configure or
read from the audio processor. It requires chip select signal CS3.
4.4.4

SSI Interface

U231
U701
U500
U302 has a total of three McBSP interfaces: McBSP1, McBSP2 and McBSP3, compatible with various
interfaces. McBSP1 is connected with I2C of the audio processor, to realize two-way transmission of
digital voice and data. McBSP2 uses independent clock and frame synchronization for transmitting
and receiving. The SSI of the receiver processor is connected with the RX end of McBSP2, and U500
with the TX end of McBSP2. U302 works in Master Mode. McBSP3 is connected with the Option Board
interface for both voice and data transmission.
BCLK
WCLK
MCBSP1.DX
SDIN
SDOUT
MCBSP1.DR
MCBSP2.CLKR
CLKOUT
FS MCBSP2.FSR
DOUTA
MCBSP2.DR
MCBSP2.CLKX
SCLK
MCBSP2.FSX
FS
MCBSP2.DX
DIN
/ LOAD
GPIO29
GPIO31
/PD

Figure 4-6 Diagram of SSI Interface

MCBSP3.CLKX
MCBSP3.FSX
MCBSP3.DX
MCBSP3.DR
MCBSP1.CLKX
MCBSP1.FSX
U302
11
Baseband Section
PCMCLK
PCMSYNC
Option Board
PCMIN
PCMOUT