Problems with softwareSerial

[lonconao]

Hello, i've had some problems using this lib with softwareserial. When i use hardwareserial no problems using libmodbus in PC side, but now, i trying access to some Iregs on ATMEGA328p with minicore (3 MHz) i cannot obtain any response from unit. For now, i have not a osciloscope for view physical port, but RE/DE pin (4 in my case) never change of state (measuring with DMM). Is possible use this library with SoftwareSerial? When use in normal way (sending strings) i don't have any problem reading data with Coolterm o any serial emulator, no data is displayed only using modbus lib in microcontroller

EDIT: I solved problem. Seems related to a custom serial flush function that unsynchronize request from master. But i have another question. If i try to define modbus regs as

const uint16_t reg1=100, reg2=101, reg3=102..., etc. server throws a error "illegal data address", but if i assign direct in object.addIreg (100, value); works properly. Any idea? Maybe uint16_t reg = 0, reg1 = 1... is the problem?