3. MICROCOMPUTER

Microcomputer TMP87CS38N-3320 has 60k byte of ROM capacity and equipped with OSD function inside.

The specification is as follow.

Type name : TMP87CS38N-3320

ROM : 60k byte

RAM : 2k byte

Processing speed : 0.5 m s (at 8MHz with Shortest com- mand)

Package : 42 pin shrink DIP

I 2C-BUS : two channels

• PWM : 14 bit x 1, 7 bit x 9

ADC : 8 bit x 6 (Successive comparison system, Conver- sion time 20ms)

IIC device controls through I2C bus. (Timing chart : See Fig. 3-1)

LED uses big current port for output only.

For clock oscillation, 8MHz ceramic oscillator is used.

I 2C has two channels. One is for EPROM only.

Self diagnosis function which utilizes ACK function of I2C is equipped

Function indication is added to service mode.

Remote control operation is equipped, and the control by set no touch is possible. (Bus connector in the con- ventional bus chassis is deleted.)

Substantial self diagnosis function

(1)B/W composite video signal generating function (micom inside, green crossbar added)

(2)Generating function of audio signal equivalent to 1kHz (micom inside)

(3)Detecting function of power protection circuit opera- tion

(4)Detecting function of abnormality in IIC bus line

(5)Functions of LED blink indication and OSD indica- tion

(6)Block diagnosis function which uses new VCD and

AV SW

SDA

 

 

 

SCL

1 - 7

8

9

 

Start

Address

R/W

Ack

condition

 

 

 

 

Approx.180μS

 

1 - 7 8 9

Data Ack

1 - 7 8 9

DATA Ack

Some device may have no data, or may have data with several bytes continuing.

Stop condition

Fig. 3-1

18

Page 18
Image 18
Toshiba TW40F80 manual Microcomputer, Sda Scl