B&B Electronics manual Timer Values, 232XS5 Smart Switch Mode Commands

SetTV$ = CHR$(27) + CHR$(2) +”T” + “6”

The “T” tells the 232XS5 it is the set timer value command and the “6” indicates which timer value to use.

Table 7 - Timer Values

Data	Value
Byte	timer disabled
0
1	10ms
2	25ms
3	100ms
4	500ms
5	1 s
6	5 s
7	30 s
8	1 min.
9	5 min.

The Set Timer Mode command tells the 232XS5 whether the time set by the Set Timer Value command will be used to determine the time-out of an inactive port, or the length of time switching commands are ignored. The third byte of the Set Timer Mode command is an ASCII “M”. If the data byte (fourth byte) is an ASCII “0”, zero (default), the timer will be setup as an inactivity timer. For example, sending the following string to the 232XS5 will set up the timer as an inactivity timer (assuming programmable character is the factory default of 2).

SetTM$ = CHR$(27) + CHR$(2) +”M” + “0”

The “M” tells the 232XS5 it is the set timer mode command and the “0” indicates to set up the timer as an inactivity timer. When the timer is configured as an inactivity timer, the 232XS5 will monitor the data lines (TD & RD) for data. If there is no activity for the specified timer value, the slave port that is connected to the master port will be disconnected. In smart switch mode, the inactivity timer can be used to prevent the preamble codes from being received by the slave devices. In port combiner mode, the inactivity timer can be used to prevent devices from tying up the master port. For example (port combiner mode), all the slave ports have their handshake lines asserted. The device on Port C has its handshake line asserted and is currently connected to the master port, but has not been transmitting or receiving data. When the inactivity timer expires, Port C will be disconnected and the next slave port will then be

232XS5-1005 Manual 11

B&B Electronics Mfg Co Inc – 707 Dayton Rd - PO Box 1040 - Ottawa IL 61350 - Ph 815-433-5100 - Fax 815-433-5104

B&B Electronics Ltd – Westlink Commercial Park – Oranmore, Galway, Ireland – Ph +353 91-792444 – Fax +353 91-792445

connected to the master port (following the first-come-first-served rule). Port C will then be placed at the “end of the line”.

If the data byte of the Set Timer Mode command is an ASCII “1”, the timer will be setup to ignore switching commands. Sending the following string to the 232XS5 will set up the timer to ignore switching commands. (Assuming programmable character is the factory default of 2).

SetTM$ = CHR$(27) + CHR$(2) +”M” + “1”

The “M” tells the 232XS5 it is the set timer mode command and the “1” indicates to set up the timer to ignore switching commands. When the timer is configured in this mode, the 232XS5 will not accept any switching commands (“A”, ”B”, ”C”, ”D”, “E”, or “EOT”) for the specified timer value. After the timer has expired, the slave port that is connected to the master port will be disconnected. This feature is useful to prevent inadvertent switching during binary/graphic type file transfers. For example (smart switch mode), the timer is configured to ignore switching commands for 5 seconds. The select Port D command is sent to the 232XS5. Once Port D is connected a file of unknown data type (so file may or may not contain a switching command sequence) is to be transferred through the 232XS5. For a period of 5 seconds after Port D is connected, no switching commands will be accepted. As long as the file transfer takes less than 5 seconds, there is no chance the 232XS5 will inadvertently switch ports.

Table 8 - 232XS5 Smart Switch Mode Commands

	Command Characters
Function	1st	2nd	3rd	4th	Comments
Select Port A	ESC	X*	“A”	NU**	Switching Command
Select Port B	ESC	X*	“B”	NU**	Switching Command
Select Port C	ESC	X*	“C”	NU**	Switching Command
Select Port D	ESC	X*	“D”	NU**	Switching Command
Select Port E	ESC	X*	“E”	NU**	Switching Command
Deselect Port	ESC	X*	EOT	NU**	Switching Command
Set Timer Value	ESC	X*	“T”	“0”-”9”	Enhanced Mode
Set Timer Mode	ESC	X*	“M”	“0”,”1”	Enhanced Mode

*X represents the programmable character set by dipswitch SW2 **NU = Not Used

12 232XS5-1005 Manual

B&B Electronics Mfg Co Inc – 707 Dayton Rd - PO Box 1040 - Ottawa IL 61350 - Ph 815-433-5100 - Fax 815-433-5104

B&B Electronics Ltd – Westlink Commercial Park – Oranmore, Galway, Ireland – Ph +353 91-792444 – Fax +353 91-792445