見るために DOS 形式の FD に ofwboot を書いて起動してみる:

 0 > boot floppy:,ofwboot /
 Unexpected Firmware Error:
 DEFAULT CATCH!, code=fff00300 at   %SRR0: 00c1b030   %SRR1: 00003030 
  ok
 0 > 

netboot と全く同じ。 一応念為:

0 > printenv load-base 
-------------- Partition: common -------- Signature: 0x70 ---------------
load-base                200000              4000 
 ok
0 > 200000 100 dump 
00200000: 7f 45 4c 46 01 02 01 00 00 00 00 00 00 00 00 00 :.ELF............:
00200010: 00 02 00 14 00 00 00 01 00 02 00 00 00 00 00 34 :...............4:
00200020: 00 00 d3 0c 00 00 00 00 00 34 00 20 00 01 00 28 :.........4. ...(:
00200030: 00 0b 00 0a 00 00 00 01 00 00 00 80 00 02 00 00 :................:
00200040: 00 02 00 00 00 00 c8 1c 00 00 ed c8 00 00 00 07 :................:
00200050: 00 00 00 10 00 00 00 00 00 00 00 00 00 00 00 00 :................:
00200060: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 :................:
00200070: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 :................:
00200080: 39 00 00 00 39 20 01 00 7d 29 03 a6 7c 00 40 ac :9...9 ..})..|.@.:
00200090: 7c 00 47 ac 39 08 00 20 42 00 ff f4 7c 00 04 ac :|.G.9.. B...|...:
002000a0: 4c 00 01 2c 3c 20 00 03 38 21 c8 90 38 21 20 00 :L..,< ..8!..8! .:
002000b0: 48 00 00 40 94 21 ff f0 7c 08 02 a6 90 01 00 14 :H..@.!..|.......:
002000c0: 7c 00 04 ac 4c 00 01 2c 3d 20 00 03 81 29 c8 1c :|...L..,= ...)..:
002000d0: 7d 29 03 a6 4e 80 04 21 7c 00 04 ac 4c 00 01 2c :})..N..!|...L..,:
002000e0: 80 01 00 14 38 21 00 10 7c 08 03 a6 4e 80 00 20 :....8!..|...N.. :
002000f0: 3c 60 00 03 3d 20 00 03 94 21 ff e0 38 63 c8 1c :<`..= ...!..8c..: ok
0 > 20000 100 dump 
00020000: 39 00 00 00 39 20 01 00 7d 29 03 a6 7c 00 40 ac :9...9 ..})..|.@.:
00020010: 7c 00 47 ac 39 08 00 20 42 00 ff f4 7c 00 04 ac :|.G.9.. B...|...:
00020020: 4c 00 01 2c 3c 20 00 03 38 21 c8 90 38 21 20 00 :L..,< ..8!..8! .:
00020030: 48 00 00 40 94 21 ff f0 7c 08 02 a6 90 01 00 14 :H..@.!..|.......:
00020040: 7c 00 04 ac 4c 00 01 2c 3d 20 00 03 81 29 c8 1c :|...L..,= ...)..:
00020050: 7d 29 03 a6 4e 80 04 21 7c 00 04 ac 4c 00 01 2c :})..N..!|...L..,:
00020060: 80 01 00 14 38 21 00 10 7c 08 03 a6 4e 80 00 20 :....8!..|...N.. :
00020070: 3c 60 00 03 3d 20 00 03 94 21 ff e0 38 63 c8 1c :<`..= ...!..8c..:
00020080: 39 29 ed c8 7c 08 02 a6 7d 23 48 50 38 80 00 00 :9)..|...}#HP8...:
00020090: bf a1 00 14 90 01 00 24 7c bd 2b 78 7d 25 4b 78 :.......$|.+x}%Kx:
000200a0: 48 00 65 5d 3d 20 00 03 93 a9 c8 1c 48 00 03 b1 :H.e]= ......H...:
000200b0: 48 00 08 d1 48 00 00 05 94 21 ff f0 3c 60 00 03 :H...H....!..<`..:
000200c0: 7c 08 02 a6 38 63 c5 bc 90 01 00 14 4b ff ff 69 :|...8c......K..i:
000200d0: 48 00 00 00 94 21 ff f0 7c 08 02 a6 3d 20 00 03 :H....!..|...= ..:
000200e0: 90 01 00 14 39 29 c5 c8 7c 60 1b 78 7d 23 4b 78 :....9)..|`.x}#Kx:
000200f0: 90 09 00 0c 4b ff ff 41 48 00 00 00 94 21 ff e0 :....K..AH....!..: ok
0 > 

load-base 200 000 に譜の内容がそのまま置いてあり、それを解釈した内容が ofwboot を作る時に指定した 20 000 に置いてある。

0 > .registers 
Client's Fix Pt Regs:
 00 00000000 00efffe0 00000000 00000000 00000000 00c1a078 00000000 00000000
 08 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
 10 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
 18 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
Special Regs:
    %IV: 00000000   %SRR0: 00020000   %SRR1: 00003000 
    %CR: 00000000     %LR: 00000000    %CTR: 00000000    %XER: 00000000 
   %DAR: 00000000  %DSISR: 00000000   %SDR1: 00fe0000 
 ok
0 > 

%SRR0 は ofwboot の開始の 20 000 になっている。