Hi sent this directly to Chris by mistake so sending again. Just to put a spanner in the works. JP's are faster in external memory.
On 25 Apr 2011, at 21:44, Chris Pile wrote: > Hi Si, > In a word... Wow! I hadn't realised there was such a performance hit using > JP over JR! > A 24T JP is painful! I've always used JP - assuming (naively) that it was > faster based on > Z80 T-state lists. > > So all these years I've been crippling my code with JPs when I should have > used JRs! Doh! > Still, it's only taken me 21-years to realise this! I've always been a bit > on the slow side! > In short, then, I guess I should ignore what Zaks is telling me regarding > T-states and simply > try to use single/double byte instructions wherever and whenever possible? > > Thanks for the info Si. It's quite an eye opener! > Chris...
