uint16_t NexDisplay::getString(const char* varName, char* text, uint16_t len)
{
  char cmd[32];
  snprintf(cmd, sizeof(cmd), NexGET, varName);
  sendCommand(cmd);
  return recvRetString(text, len);
}
uint16_t NexButton::getText(char *buffer, uint16_t len)
{
    String cmd;
    cmd += "get ";
    cmd += getObjName();
    cmd += ".txt";
    sendCommand(cmd.c_str());
    return recvRetString(buffer,len);
}