Datasheet

EA eDIPTFT70-A
Page 4
ELECTRONIC ASSEMBLY reserves
the right to change specifications
without prior notice. Printing and
typographical errors reserved.
RS-232 INTERFACE
If the display is wired as shown below,
the RS-232 interface is selected. The
pin assignment is specified in the table
on the right.
The RxD and TxD lines lead CMOS
level (5V) for direct connection to a
microcontroller for example.
If “genuine” RS-232 levels are required
(e.g. for connection to a PC), an
external level converter (e.g. MAX232)
is required.
Baudraten
Baud0 Baud1 Baud2
Datenformat
8,N,1
1 0 0
2400
0 1 0
4800
1 1 0
9600
0 0 1
19200
1 0 1
38400
0 1 1
57600
1 1 1
115200
0 0 0
230400
Note:
The pins BAUD 0 to 2, ADR 0 to 2, DPOM,
DPROT and TEST/SBUF have an internal
pullup, which is why only the LO level
(0=GND) is to be actively applied. These
pins must be left open for a Hi level.
For RS232 operation (without
addressing) the pins ADR 0 to ADR 2
must be left open.
On pin 20 (SBUF) the display indicates
with a low level that data is ready to be
retrieved from the internal send buffer.
The line can be connected to an interrupt
input of the host system, for example.
BAUD RATES
The baud rate is set by means of pins 6, 7 and 8 (baud 0 to 2). The data
format is set permanently to 8 data bits, 1 stop bit, no parity.
RTS/CTS handshake lines are not required. The required control is
taken over by the integrated software protocol (see pages 10 and 11).
application example
Pinout eDIPTFT70-A: RS-232/RS-485 mode
Pin Symbol In/Out Function Pin Symbol In/Out Function
1 GND Ground Potential for logic (0V) 25
NC do not connect, reserved
2 VDD Power supply for logic (+5V) 26
3 SND+ Speaker LS1 (Impedance 8 Ohm) 27
4 SND- Speaker LS2 28
5 RESET In L: Reset 29 GND Ground (=Pin 1)
6 BAUD0 In Baud Rate 0 30 VDD Power supply (=Pin 2)
7 BAUD1 In Baud Rate 1 31 AIN1
In
analogue input 0..VDD
DC impedance 1MOhm
8 BAUD2 In Baud Rate 2 32 AIN2
9 ADR0 In Address 0 for RS-485 33 OUT1 / MO8
Out
8 digital outputs
maximum current:
IOL = IOH = 10mA
alternativ up to 8 matrix
keyboard output lines
(reduces the digital output
lines, see chapter external
keyboard)
10 RxD In Receive Data 34 OUT2 / MO7
11 TxD Out Transmit Data 35 OUT3 / MO6
12 EN485 Out Transmit Enable for RS-485 driver 36 OUT4 / MO5
13 DPOM In
L: disable PowerOnMacro
do not connect for normal operation
37 OUT5 / MO4
14 ADR1 In Address 1 for RS-485 38 OUT6 / MO3
15 ADR2 In Address 2 for RS-485 39 OUT7 / MO2
16 BUZZ Out Buzzer output 40 OUT8 / MO1
17 DPROT In
L: Disable Smallprotokoll
do not connect for normal operation
41 IN1 / MI8
In
8 digital inputs
open-drain with internal
pullup 20..50k
alternativ up to 8 matrix
keyboard input lines
(reduces the digital input
lines, see chapter external
keyboard)
18 DNC Out L: internal, do not connect 42 IN2 / MI7
19 WP In L: Writeprotect for DataFlash 43 IN3 / MI6
20
TEST
SBUF
IN
Out
open-drain with internal pullup 20..50k
IN (Power-On) L: Testmode
OUT L: data in sendbuffer
44 IN4 / MI5
21
N.C. do not connect, reserved
45
IN5 / MI4
22 46
23 47
24 48