Reload the first 256 bytes of FLASH memory

The syntax of the "B" command is:
B0
Notes:
  No distinction is made between uppercase and lowercase.
  The command is only accepted in Manager or Administrator mode.

That's it - just "B0", or "$B0" to logon in Manager Mode and send the command, all on one command line. This command reinitializes the first 256 bytes of FLASH, or PROGRAM, memory with the a 256-byte block that are located in the protected Operating System FLASH memory. Actually, that 256 byte block is the highest readable FLASH memory has the following ranges in MIRTOS Version 3.01: 0x3F00 to 0x3FFF in the 328P, 0x1AE00 to 0x1AEFF in the 1284P, and 0x3AC00 to 0x3ACFF in the 2560.
>DP+ 0 256
FLASH (program memory) contents:
0000:  FF FF FF FF FF FF FF FF-FF FF FF FF FF FF FF FF  ................
0010:  FF FF FF FF FF FF FF FF-FF FF FF FF FF FF FF FF  ................
0020:  FF FF FF FF FF FF FF FF-FF FF FF FF FF FF FF FF  ................
0030:  FF FF FF FF FF FF FF FF-FF FF FF FF FF FF FF FF  ................
0040:  FF FF FF FF FF FF FF FF-FF FF FF FF FF FF FF FF  ................
0050:  FF FF FF FF FF FF FF FF-FF FF FF FF FF FF FF FF  ................
0060:  FF FF FF FF FF FF FF FF-FF FF FF FF FF FF FF FF  ................
0070:  FF FF FF FF FF FF FF FF-FF FF FF FF FF FF FF FF  ................
0080:  FF FF FF FF FF FF FF FF-FF FF FF FF FF FF FF FF  ................
0090:  FF FF FF FF FF FF FF FF-FF FF FF FF FF FF FF FF  ................
00A0:  FF FF FF FF FF FF FF FF-FF FF FF FF FF FF FF FF  ................
00B0:  FF FF FF FF FF FF FF FF-FF FF FF FF FF FF FF FF  ................
00C0:  FF FF FF FF FF FF FF FF-FF FF FF FF FF FF FF FF  ................
00D0:  FF FF FF FF FF FF FF FF-FF FF FF FF FF FF FF FF  ................
00E0:  FF FF FF FF FF FF FF FF-FF FF FF FF FF FF FF FF  ................
00F0:  FF FF FF FF FF FF FF FF-FF FF FF FF FF FF FF FF  ................
>   ; The first 256 bytes of FLASH were reset (above); type "$" to login
m>B0
m>DP+ 0 256
FLASH (program memory) contents:
0000:  0C 94 80 30 10 02 43 6F-70 79 72 69 67 68 74 2C  ...0..Copyright,
0010:  20 32 30 31 33 2D 32 30-32 32 2C 20 53 43 41 44   2013-2022, SCAD
0020:  41 20 53 75 70 70 6F 72-74 20 47 72 6F 75 70 2C  A Support Group,
0030:  20 49 6E 63 2E 0D 0A 53-6F 6E 6F 6D 61 2C 20 43   Inc...Sonoma, C
0040:  41 20 39 35 34 37 36 20-20 ## ## ## 2E ## ## ##  A 95476  ###.###
0050:  2E ## ## ## ## 0D 0A 4D-49 52 54 4F 53 20 66 6F  .1232..MIRTOS fo
0060:  72 20 31 36 20 4D 48 7A-20 41 72 64 75 69 6E 6F  r 16 MHz Arduino
0070:  20 50 72 6F 20 4D 69 6E-69 0D 0A 56 65 72 73 69   Pro Mini..Versi
0080:  6F 6E 20 33 2E 30 31 20-2D 20 4D 6F 6E 64 61 79  on 3.01 - Monday
0090:  2C 20 4D 61 72 63 68 20-32 38 2C 20 32 30 32 32  , March 28, 2022
00A0:  0D 0A 00 00 00 00 00 00-00 00 00 00 00 00 CA 9A  ................
00B0:  3B 00 E1 F5 05 80 96 98-00 40 42 0F 00 A0 86 01  ;........@B.....
00C0:  00 10 27 00 00 E8 03 00-00 64 00 00 00 0A 00 00  ..'......d......
00D0:  00 53 65 72 69 61 6C 20-4E 75 6D 62 65 72 3A 20  .Serial Number:
00E0:  ## ## ## ## ## ## ## ##-## 00 8B DD 02 15 23 21  #########.....#!
00F0:  52 3F A0 02 42 AB DF 56-0E 79 C3 84 1A A4 FF FF  R?..B..V.y......
m>                                                                              
This block of FLASH memory contains the individual Serial Number for the device, which must be valid for MIRTOS to enable the functions defined in EEbSystemMode. The system will also display the low six (6) bits of the Seconds value in the LEDs and discrete outputs (PORTC, bits 0 through 5) whenever it is unable to verify the Serial Number in this block.

See also:
  The Erase FLASH Command and the EraseFLASHPage and Read_PGM System Commands.