Compaq Contec COM-2(PC)F - Manual (Page 62)

Appendix
COM-2(PC)F
53
Sample Program 9
[Half-duplex data reception (Enhanced mode)]
The sample program 9 enables initialization on ACE, receives
5-byte data; after transmission, the program enters the transmission
mode for data transmission.
No
Yes
1
Line Status
D0 bit = 1
Set Baud Rate
Generator
1
Set Interrupt Enable
Register
Set Transmission Format
(Line Control Register)
WAIT Time
(After Initialization)
Set Modem
Control Output
Read
Line Status Register
Read
Interrupt ID Register
Read
Received Data Register
5 bytes Receive
Line Status
D6 bit = 1
Data Transmittion
Transmit end
START
END
No
Yes
No
Yes
No
Yes
1 Note: Wait Time = (sec)
Data Length
Baud Rate
Read
Modem Status Register
Modem Control
RTS to LOW
Modem Control
RTS to High
5 bytes Transmit
No
Display Receiver Buffer's
Data 0n CRT
1
Yes
Figure 6.11. Flowchart of Sample Program 9