H8/3048 Flash or ROM read command line


New to this MCU and have some experience with embedded systems, please help. Is it possible to read Flash of a H8/3048 and how? I can only write to Flash ( in boot mode)  and read and write to EEPROM in normal mode (via the serial port and command terminal using known r/w commands and memory locations for EEPROM ).

To write to flash from 00000000 to 0001FFFF I use  Flash 5 windows s/w but the app does not read from flash. I am hoping to be able and read the flash from a serial port mode in the same way I do with EEPROM ( or some other way ). I know that a standalone  H8/3048 programmer can do this but I have no means of removing the MCU from PCB and do it in that way.

If not possible to read flash in boot mode, would it be possible to get the same data somewhere from ROM in normal mode?

Just trying to get my old jetski ECU running again...

Thank you.