On 8 Mar 2007, at 19:10, Daniele Terdina wrote: >> The easiest way to distinguish between 68020+ and the others is: >> >> MOVEM.L A7,-(A7) >> CMPA.L (A7),A7 >> ADDQ.L #4,A7 ;Reset A7 and leave condition codes >> unaltered >> BEQ LOW ;Not 68020+ > > Interesting... this seems to be the opposite of what the M680x0 > programmer's > manual states: > "If the effective address is specified by the predecrement > mode ... ... For > the MC68020, MC68030, MC68040, and CPU32, if the addressing > register is also > moved to memory, the value written is the initial register value > decremented > by the size of the operation. The MC68000 and MC68010 write the > initial > register value (not decremented)." >
It is quite possible that I have set BEQ instead of BNE. This does not alter the principle of the method, which I learnt from Simon Goodwin. George _______________________________________________ QL-Users Mailing List http://www.q-v-d.demon.co.uk/smsqe.htm
