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3.2 Basic Communications Specifica-
tions and Parameters
3.2.1 Basic Communications Specifications
Listed below are the communications specifications when the BHT-6000 exchanges
data with a host computer through the CU-6000 (optical interface) or direct-connect
interface cable.
Direct-connect Interface
Synchronization
Transmission Speed
Transmission Code
Transmission Bit Order
Response Method
Transparency
Vertical Parity
JIS 8-bit codes
Optical Interface
2400, 9600, 19200, 38400,
57600, or 115200 bps
■ Synchronization
For accurate data transaction, it is very important to synchronize the transmission
between the sender and receiver. To do this, it is required to previously define the
bit order and position, the character length, and the beginning and end of the
character to be transmitted.
The start-stop synchronization is an asynchronous system which synchronizes
each character as a unit; that is, it externally adds start and stop bits to the leading
and trailing bit positions of the character to be transmitted, respectively. A clock
starts counting on receiving the start bit and it falls into a non-communication state
on receiving the stop bit. The number of the stop bits is selectable (1 or 2 bits).
■ Transmission Speed
Maximum number of bits to be transmitted per second. Expressed in bps (bits per
second).
■ Optical Interface Communications Range
The optical interface's maximum effective range is 80 cm with the IR beam within a
10˚ angle of divergence.
300, 600, 1200, 2400, 4800, 9600,
19200, or 38400 bps
JIS 7- or 8-bit codes
None Even, odd, or none
Start-stop
LSB (Least significant bit) first
Transparent or non-transparent mode
ACK/NAK response