- status = ul_read(startconfigblock, ulev1_conf, sizeof(ulev1_conf));
- if ( status == -1 ) {
- PrintAndLog("Error: tag didn't answer to READ EV1");
- ul_switch_off_field();
- return status;
- } else if (status == 16) {
- // save AUTHENTICATION LIMITS for later:
- authlim = (ulev1_conf[4] & 0x07);
- ulev1_print_configuration(ulev1_conf);
- } else {
- authlim=7;
+ if (startconfigblock){ // if we know where the config block is...
+ status = ul_read(startconfigblock, ulev1_conf, sizeof(ulev1_conf));
+ if ( status == -1 ) {
+ PrintAndLog("Error: tag didn't answer to READ EV1");
+ ul_switch_off_field();
+ return status;
+ } else if (status == 16) {
+ // save AUTHENTICATION LIMITS for later:
+ authlim = (ulev1_conf[4] & 0x07);
+ ulev1_print_configuration(ulev1_conf);
+ }