ICD-MS1 (serv.man2) - Sony Audio Service Manual (repair manual). Page 5

Copying is strictly prohibited 

5

 

Fig. 1-2 shows the microprocessor interface of this unit. 
 
1.    Communication between System Controller IC722 and ADPCM CODEC IC164 
The system controller IC722 controls the ADPCM IC164 by outputting the serial commands. These serial commands are output from pin-69 [TXD2] of the system controller 
IC722 in synchronization with the clock of pin-70 [SCK2] of the system controller IC722. The selection of LP/SP and control of playback speed are performed by changing the 
output frequency of pin-159 [SYNC] of the system controller IC722 
 
The main interface is described as follows. 

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Communication between system controller IC722 and ADPCM CODEC IC164 :   

•  Selection of the various modes (Record/Playback) of the signal processing block   

•  Selection of the recording modes (SP/LP) during recording 

SP : 11 kHz, 3 bits/LP : 8 kHz, 2 bits 

•  Control of the speed control during playback, and others. 

 
2.    Communication between System Controller IC722 and LCD Module (LCD720) 
The system controller IC722 outputs the data to be displayed on the LCD from pin-24 [LCD DO] while synchronizing it with the clock of pin-78 [LCD SCK]. Thus IC722 drives 
the LCD module. The system controller IC722 has the signal input terminal of pin-25 [LCD DI] that is not used at present. 
 
3.    Communication between System Controller IC722 and REAL TIME CLOCK (Timer) IC721 
The system controller IC722 outputs the data such as watch setup data from pin-69 [TXD2] to pin-7 [DATA] of the RTC (REAL TIME CLOCK) IC721 in synchronization with the 
clock of pin-70 [SCK2] and the chip select signal of pin-17 [RTC CE]. At the startup of this unit, RTC IC721 outputs the watch information that is based on the received data, to 
pin-68 [RXD2] of the system controller IC722 in synchronization with the clock of pin-70 [SCK2] and the chip select signal of pin-17 [RTC CE] of the system controller IC722. By 
this communication, the system controller IC722 obtains the watch information. RTC IC721 also outputs the timer interrupt output such as alarm, and others to pin-149 
[RTCINT1] and pin-148 [RTCINTR] of the system controller IC722 from pin-4 [/AIRQ] and pin-5 [/TIRQ] of the RTC IC721. This output is connected to the wake-up detection 
circuit that starts up the unit at the timer's preset time. When the unit starts up by the timer, the corresponding audio data, priority, title, alarm information and other data that 
have already been saved in the Memory Stick, are read out from the Memory Stick to the RAM area inside the system controller and are used. 
 
4.    Communication between System Controller IC722 and EEP ROM IC723 
The EEP ROM IC723 stores the information that is set from the menu. In order to read the necessary data from the EEP ROM, the system controller IC722 outputs the serial 
data (read command) from pin-69 [TXD2] of the system controller IC722 to pin-3 [DI] of the EEP ROM IC723 in synchronization with the clock of pin-70 [SCK2] and the chip 
select signal of pin-1 [XEPCS] of the system controller IC722. When the EEP ROM IC723 receives the read command, it outputs the corresponding data from pin-4 [DO] to 
pin-68 [RXD2] of the system controller IC722. 
 
5.    Communication between System Controller IC722 and Memory Stick 
The system controller IC722 performs the serial communication with the controller that is installed inside the Memory Stick. The system controller IC722 outputs the various 
commands to the Memory Stick from pin-12 [MS DIO] in synchronization with the clock output from pin-13 [MS CLK] and the bus state signal output from pin-11 [MS BS]. Role 
of the controller inside the Memory Stick is described next. In order to read data from the Memory Stick, the controller inside the Memory Stick receives the data read command 
first. Then it reads the data corresponding to the read command, from the FLASH RAM area inside the Memory Stick. The controller inside the Memory Stick then converts the 
read-out data to the serial data and outputs it to the system controller IC722 in synchronization with the clock input from the system controller IC722 and the bus state signal. 
The system controller IC722 converts the received data to the parallel data by its DMA controller and outputs the data to the 2M-bit S-RAM IC727 sequentially. In order to write 
data into Memory Stick, the system controller IC722 outputs the data to be written in the controller inside the Memory Stick in the same manner as in reading, in synchronization 
with the clock and bus state signal. The controller inside the Memory Stick that receives the data to be written, converts it to the parallel data and saves it in the FLASH RAM 
area inside the Memory Stick.