
Table 3 - Timer Values
Data Byte | Value |
|
|
0 | timer disabled |
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 requires the third byte to be 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 232MSS2 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 232MSS2 it is the set timer mode command and the “0” indicates to set up up the timer as an inactivity timer. When configured as an inactivity timer, the 232MSS2 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 connected to the master port (following the
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 232MSS2 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”
10 | Documentation Number |
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