Hmm.. Ztan, can you have a look at the following code - normally, the SSMGet routines fetch a float direct parameter, run it through a makeuint 8 or makeuint16 subroutine, and pop out the SSM parameter - this is the way MAF voltage is pulled in the SH7058 roms.
This one pulls another subroutine, which I have not had the patience to pull apart in understanding
Maybe you can have a look?
here is the SSMGet routine:
Code:
ROM:000842BC SsmGet_Mass_Airflow_Sensor_Voltage_P18: ; DATA XREF: ROM:00097234o
ROM:000842BC movmu.l r14, @-r15 ; Move Multi-register Upper part
ROM:000842BE mov r4, r14 ; Move Data
ROM:000842C0 mov.l #sub_12FCC, r2 ; Move Immediate Long Data
ROM:000842C2 jsr @R2 ; sub_12FCC ; Jump to Subroutine
ROM:000842C4 mov #h'2C, r4 ; ',' ; Move Immediate Byte Data
ROM:000842C6 extu.w r0, r6 ; Extend as Unsigned (Word)
ROM:000842C8 lds r6, fpul ; Load to System Register
ROM:000842CA float fpul, fr4 ; Floating-point convert from integer
ROM:000842CC mova flt_84464, r0 ; Move Effective Address
ROM:000842CE fmov.s @r0, fr8 ; Floating-point move single precision
ROM:000842D0 fmul fr8, fr4 ; Floating-point multiply
ROM:000842D2 mov.l #ConvertTo_uint8, r2 ; Move Immediate Long Data
ROM:000842D4 fldi0 fr6 ; Floating-point load immediate 0.0
ROM:000842D6 mova flt_84468, r0 ; Move Effective Address
ROM:000842D8 jsr @R2 ; ConvertTo_uint8 ; Jump to Subroutine
ROM:000842DA fmov.s @r0, fr5 ; Floating-point move single precision
ROM:000842DC mov.b r0, @r14 ; Move Byte Data
ROM:000842DE movmu.l @r15+, r14 ; Move Multi-register Upper part
ROM:000842E0 rts/n ; Return from Subroutine with No delay slot
And this is the subroutine it jumps to:
Code:
ROM:00012FCC sub_12FCC: ; CODE XREF: sub_2A822+18p
ROM:00012FCC ; sub_2AD74+Cp ...
ROM:00012FCC
ROM:00012FCC var_8 = -8
ROM:00012FCC var_7 = -7
ROM:00012FCC
ROM:00012FCC sts.l pr, @-r15 ; Store System Register Long
ROM:00012FCE add #-4, r15 ; Add binary
ROM:00012FD0 mov.w r4, @r15 ; Move Word Data
ROM:00012FD2 movu.b @(0,r15), r0 ; Move Structure Byte Data as Unsigned
ROM:00012FD6 tst r0, r0 ; Test Logical
ROM:00012FD8 bt loc_12FE6 ; Branch if True
ROM:00012FDA cmp/eq #1, r0 ; Compare: Equal
ROM:00012FDC bt loc_12FF2 ; Branch if True
ROM:00012FDE cmp/eq #2, r0 ; Compare: Equal
ROM:00012FE0 bt loc_12FFE ; Branch if True
ROM:00012FE2 bra loc_1300A ; Branch
ROM:00012FE4 nop ; No Operation
ROM:00012FE6 ; ---------------------------------------------------------------------------
ROM:00012FE6
ROM:00012FE6 loc_12FE6: ; CODE XREF: sub_12FCC+Cj
ROM:00012FE6 mov.b @(1,r15), r0 ; Move Structure Byte Data
ROM:00012FE8 mov.l #sub_129C4, r1 ; Move Immediate Long Data
ROM:00012FEA jsr @r1 ; sub_129C4 ; Jump to Subroutine
ROM:00012FEC mov r0, r4 ; Move Data
ROM:00012FEE bra loc_1300C ; Branch
ROM:00012FF0 mov r0, r2 ; Move Data
ROM:00012FF2 ; ---------------------------------------------------------------------------
ROM:00012FF2
ROM:00012FF2 loc_12FF2: ; CODE XREF: sub_12FCC+10j
ROM:00012FF2 movu.b @(1,r15), r0 ; Move Structure Byte Data as Unsigned
ROM:00012FF6 mov.l #unk_FFF848FE, r5 ; Move Immediate Long Data
ROM:00012FF8 shll r0 ; Shift Logical Left
ROM:00012FFA bra loc_1300C ; Branch
ROM:00012FFC mov.w @(r0,r5), r2 ; Move Word Data
ROM:00012FFE ; ---------------------------------------------------------------------------
ROM:00012FFE
ROM:00012FFE loc_12FFE: ; CODE XREF: sub_12FCC+14j
ROM:00012FFE movu.b @(1,r15), r0 ; Move Structure Byte Data as Unsigned
ROM:00013002 mov.l #unk_FFF8490E, r6 ; Move Immediate Long Data
ROM:00013004 shll r0 ; Shift Logical Left
ROM:00013006 bra loc_1300C ; Branch
ROM:00013008 mov.w @(r0,r6), r2 ; Move Word Data
ROM:0001300A ; ---------------------------------------------------------------------------
ROM:0001300A
ROM:0001300A loc_1300A: ; CODE XREF: sub_12FCC+16j
ROM:0001300A mov #0, r2 ; Move Immediate Byte Data
ROM:0001300C
ROM:0001300C loc_1300C: ; CODE XREF: sub_12FCC+22j
ROM:0001300C ; sub_12FCC+2Ej ...
ROM:0001300C add #4, r15 ; Add binary
ROM:0001300E lds.l @r15+, pr ; Load to System Register Long
ROM:00013010 rtv/n r2