8. FREQUENTLY ASKED QUESTIONS (FAQ)
Q1: | What is the flow control method recommended? |
A1: | If the host is a PC, Hardware flow control is recommended. |
| However, in most control instrumentation, either software or no flow control is |
| called for. |
Q2: | How do I disable any flow control? |
A2: | Simply disable both the Hardware and software control switch settings. This is |
| not recommended for large file transfers. |
Q3: | I need to connect the Cellular Data Link to a machine, which does not |
| understand your messages. All it needs is data. Which configuration is |
| recommended? |
A3: | Please use the ATQ1&w&w1<CR> command. |
Q4: | Have you experienced unreliable communication with certain modems? |
A4: | Yes. Several generic brands tend to throw hot signals (i.e. strong signal levels) |
| on the line. This causes the cellular service to |
| distortions and results in unreliable connections. |
Q5: | What is the solution? |
A5: | We recommend that you use modems that support |
| transmit level to be reduced to between |
| modem designs generally meet these requirements. |
For Rockwell based modems, please try the following commands on the land line modem:
∙
∙AT+MS=11,1,1200,2400X3&W&W1<CR>. Sets the modem to communicate between 1200 and 2400 bps.
Q6: | Is there any simple way to avoid frequent loss of connection? |
A6: | Please program the CMM |
| AT+MS=11,1,1200,1200&W&W1<CR> |
| This will force the CMM |
Q7: | What initialization string is recommended to communicate with |
| modems? |
A7: | Connection with |
| Page 16 of 16 |