Epson TM U200D - B/W Dot-matrix Printer Technical Manual page 34

When the ASB status is received following this, a total of eight (8) bytes of ASB will be
transmitted as follows:
Accumulated ASB ( + + )
Accumulated ASB (
+
The latest ASB ( )
Fourth Status
Notes on setting DIP switch 1-8 to ON
The printer mechanism stops but does not become busy when an error has occurred, printing
stops due to a paper end, or paper is fed using the FEED button.
When setting DIP switch 1-8 to ON to enable handshaking with the printer, be sure to check the
printer status with GS a and ASB function. In this setting, the default value of n for GS a is 2.
The printer automatically transmits the printer status, depending on on-line/off-line changes.
When using DLE EOT and DLE ENQ, be sure that the receive buffer does not become full.
When using a host that cannot transmit data when the printer is busy and if an error occurs,
DLE EOT and DLE ENQ cannot be used when printer is busy due to receive buffer-full
state.
If the host can transmit data when the printer is busy and, the receive buffer becomes full
while the host is sending bit-image data, a DLE EOT or DLE ENQ command used while
sending bit-image data is processed as bit-image data, not as a command. Secondly, any
data transmitted when the receive buffer is full may be lost.
Example: Check the printer status using GS r after transmitting each line of data and use the 1K
byte receive buffer. Transmit one line of data so that the receive buffer does not become full.
1-22 Features and General Specifications
First Status Second Status
0001 0000 0000 0000
0101 1000 0000 0000
0001 0000 0000 0000
First Status
+ +
) 0101 0000
First Status
0001 0000
Third Status Fourth Status
0000 0000 0000 0000
0000 0011 0000 0000
0000 0011 0000 0000
Second Status Third Status
0000 0000 0000 0000
Second Status Third Status
0000 0000 0000 0000
Near end
detection
FEED button is
pressed
FEED button is
released
Fourth Status
0000 0000
Fourth Status
0000 0000
Rev.B