beautypg.com

Serial interface, Initialization, Epson stylus color 500 – SUPER MICRO Computer Epson Stylus Color 500 User Manual

Page 5

background image

EPSON Stylus COLOR 500

Ink Jet Printers

6/96

EPSON Stylus COLOR 500 - 5

The following table lists the parallel connector pin assignments
and describes their respective interface signals.

Note:
The column heading “In/Out” refers to the direction of the signal flow
as viewed from the printer.

Timing chart

The figure below shows the timing chart for the parallel
interface.

Transition time (both the rise and the fall) of every signal must be less than
0.2

µ

s.

Serial Interface

The printer’s built-in serial interface is based on the RS-422
standard so you can connect the printer to an Apple Macintosh.

Standard:

Based on RS-422

Synchronization: Asynchronous

Bit rate:

57.6 Kbps/230.4 Kbps

Handshaking:

DTR protocol

Word format:

Data bit

8 bits

Parity bit

None

Start bit

1 bit

Stop bit

1 bit

Connector:

8-pin mini-circular connector

Recommended
cable:

Apple System Peripheral-8 cable (M0197)

Initialization

The printer can be initialized (returned to a fixed set of
conditions) in these ways:

Each initialization method resets the font according to the
default settings selected using the control panel. However,
ESC @ does not initialize the printer mechanism, clear the input
data buffer, or clear the user-defined character set.

Pin
no.

Signal name

GND

In/Out

Description

1

HostClk

19

In

Strobe pulse. Input data is latched
at falling edge of the signal.

2

DATA 1

20

In

Bit 0: LSB Parallel input data to the
printer.

3

DATA 2

21

In

These signals represent information
in bits 0 to 7 of parallel data
respectively. Each signal is at HIGH
level when data is logical 1 and LOW
when it is logical 0. These signals
are used to transfer the 1284
extensibility request values to the
printer.

4

DATA 3

22

In

5

DATA 4

23

In

6

DATA 5

24

In

7

DATA 6

25

In

8

DATA 7

26

In

9

DATA 8

27

In

10

PtrClk

28

Out

Used to qualify data being sent to
the host. Set LOW then HIGH to
cause an interrupt indicating to host
that data is available.

11

PtrBusy/
DataBit-3,7

29

Out

Data bits 3 then 7 indicate forward
channel busy status.

12

ACkDataReq/
DataBit-2,6

28

Out

Data bits 2 then 6. Set HIGH until
host requests data transfer, then
follows nData Avail (nFault).

13

Xflag/
DataBit-1,5

28

Out

X-flag signal and reverse channel
transfer data bit 1 then 5.

14

HostBusy

30

In

Set LOW to indicate that host can
receive peripheral device to host
data. Then set high to acknowledge
receipt of that nibble. Set high in
response to PtrClk (nAck) low pulse
to re-enter reverse data transfer
phase.

31

INIT

30

In

Not used

32

DataAvail./
DataBit-0,4

29

Out

This signal is LOW when the printer
is in an error state

36

1284-Active

30

In

1284 active signal

18

Logic H

-

Out

Pulled up to +5V through 3.9 k

resistance.

35

+5V

-

Out

Pulled up to +5V through 3.3 k

resistance.

17

Chassis

-

-

Chassis GND

16,33,
19–30

GND

-

-

Signal GND

15, 34

NC

-

-

Not connected

Hardware
initialization

• The printer is turned on.
• The printer receives an INIT signal

from the parallel interface: pin 31 goes LOW

Software
initialization

• Software sends the ESC @ (initialize the printer)

command; the last panel settings are kept

BUSY

DATA

0.5

µ

s (Min.)

0

µ

s (Min.)

5

µ

s (Typ.)

0

µ

s (Min.)

ACKNLG

STROBE