16T202DA1J Datasheet, PDF (11/18 Pages) Samsung semiconductor – VACUUM FLUORESCENT DISPLAY MODULE

SDI
16T202DA1J (Rev 1.0)
Page 11 / 18
5.2 Interfacing to the MPU
This VFD module can interface in either two 4-bit operations or one 8-bit operation, thus allowing
interfacing with 4- or 8-bit MPUs.
* For 4-bit interface data, only four bus lines (DB4 to DB7) are used for transfer. When to use 4-bit
parallel data transfer, DB0 to DB3 keep "H" or "L". The data transfer between the VFD module and
the MPU is completed after the 4-bit data has been transferred twice. As for the order of data transfer
the four high order bits (for 8-bit operation, DB4 to DB7) are transferred before the four low order bits
(for 8-bit operation, DB0 to DB3).
The busy flag (BF) are performed before transferring the higher 4 bits. BF checks are not required
before transferring the lower 4 bits.
RS
R/W
E
DB7
DB6
DB5
DB4
IR7 IR3
D7 D3
BF
AC3
DR7 DR3
IR6 IR2
D6 D2
AC6
AC2
DR6 DR2
IR5 IR1
D5 D1
AC5
AC1
DR5 DR1
IR4 IR0
Instruction Register
Write
D4 D0
Character Code
Write
AC4
AC0
Busy Flag & Address
Counter Read
DR4 DR0
Data Register
Read
Fig-11 4-Bit Transfer Example (M68)
* For 8-bit interface data, all eight bus lines (DB0 to DB7) are used.
D7 D3
D6 D2
D5 D1
D4 D0
Character Code
Write
5.3 Reset Function
5.3.1 Power-on reset
An internal reset circuit automatically initializes the module when the power is turned on.
The following instructions are executed during the initialization.
1) Display clear
Fill the DD-RAM with 20H (Space Code)
2) Set the addres counter to 00H
Set the address counter (ACC) to point DD-RAM.
3) Display on/off control:
D = 0 ; Display off
C = 0 ; Cursor off
B = 0 ; Blinking off
4) Entry mode set:
I/D = 1 ; Increment by 1
S = 0 ; No shift
5) Function Set
IF = 1 ; 8-bit interface data
N = 1 ; 2-line display
BR0 = BR1 =0 ; Brightness = 100%
6) CPU interface type
when JP0 = Open ; M68 type (Factory Setting)
when JP0 = Short ; i80 type