Motorola V3229 Operating Instructions - Page 137

S-REGISTERS 6 Status Registers Chapter 6 Status Registers Most modem configuration information is stored in a part of memory called status (S) registers. During operation this information is used to determine modem functions. The information stored in the S-registers is changed by the AT or V.25b command sets and by pushbuttons in response to the LCD prompt. These are the preferred methods. Some software programs also access the S-registers via the AT command set, but this action is transparent to the user. The ATS commands indicate which memory bit(s) to alter to select a particular option or to perform a certain function. The S-register values comprise the configuration profile. Caution: The purpose of this tutorial is to show the versatility of option selection and register function. It is strongly recommended that the preferred methods of option selection be used. This tutorial uses S22 as the example register. Certain modems may use S22 differently or may not have an S22. Generally the user should not directly alter S-register values. However, the user has the option of changing S-registers via ATS commands and directly altering the register value. This is called "writing" to the Sregister. Writing to an S-register is not a preferred method and should only be used by programmers who need to manipulate S-registers so they can interact with a software program under development or some other similar action. V.3229 / V.3229L -1