FV-DB1E (serv.man3) - Sharp Audio Service Manual (repair manual). Page 18

FV-DB1E

7 – 2

The asynchronous serial port carries asynchronous serial characters
over two wires (TxD, RxD) at data rates up to 115 kbit/s. In this particu-
lar application it can be used to control the module in ‘slave’ mode.
The default baud rate is 115 kbit/s.

A USB 1.1 interface (slave) is carried over two wires. The USB inter-
face will support data transfers at up to 12 Mbits/s.

The Serial Control Bus consists of a two wire, open collector bus. This
bus is a master only, and may be used for controlling other devices in
the system.

A single PDM (Pulse Density Modulated) output can be provided for
generation of a low resolution analogue output. This may be used for
control of display brightness for example.

LCD display data is presented on 8 data lines, with 4 timing control
lines to synchronize transfers. The LCD port will support both alphanu-
meric and graphic LCDs. If a LCD connection is not required, then
these lines may be used as GPIO.

NOTE: Ideally, the LCD controller should be powered from the 3V3

supply. If a 5 V LCD module is used it should have its own
supply rail and should not be connected to the 5 V RF supply
as any conducted noise will degrade RF sensitivity.

All the above signals (excluding USB, I

2

S control and stereo out) may

be used as GPIO signals. The state of each GPIO signal can be read
by software. The logic level and tri-state drive of each GPIO signal can
also be controlled by software.

The following table specifies the main pin functions, identifies which of
these can be used as GPIO lines, and also defines an example DAB
product function based on the reference MMI software.

The Reference MMI software assigns the following button mapping for
the keypad matrix:

Alphanumeric mode: 4-bit or 8-bit data transfers.

Compatible with displays using Hitachi 
HD44780, Samsung S6A0069X (KS0066) or 
similar controllers.

Graphic mode:

4-bit or 8-bit data transfers.
4 control signals (date clock, line clock, frame 
clock, polarity reversal) compatible with wide 
range of graphic display controllers.

S/PDIF Output

A11

12

S/PDIF Output

S/PDIF Input

A0

37

Keypad row 3

RDI Output

A10

38

Keypad row 4

S1_DIN

D3

15

S1_DOUT

D2

16

USB_DP

No

9

USB_DP

USB_DM

No

8

USB_DM

SCP_CLK

A9

39

IR remote activity LED

SCP_DAT

A8

40

IR receiver input

PDM Output

A7

41

Keypad column 3

LCD_DATA<7..0>

B<15..8>

25-32

LCD_DATA<7..0>

LCD_F

C1

33

Keypad row 2

LCD_LRS

C2

34

LCD_RS

LCD_M

C0

35

Keypad row 1

LCD_PE

C3

36

LCD_E

AUD_SFR

No

21

AUD_SFR

AUD_SCLK

No

23

AUD_SCLK

AUD_MCLK

No

24

AUD_MCLK

AUD_SDOUT0

No

22

AUD_SDOUT0

AUD_SDOUT1

A1

42

Keypad column 1

AUD_SDOUT2

A2

43

Keypad column 2

AUD_SDIN

A12

44

Keypad column 4

scroll_up

scroll_down

Select

preset 1

display

info

Scan

preset 2

volume_up

volume_down Mute

preset 3

power

factory_rst

preset 4

preset 5