troed wrote: Tue Jun 23, 2020 11:42 pm
With a CPLD on the bus it shouldn't be too hard to make it Mega ST compatible though? Then TOS would indeed support it.
Job for you then
The RTC chips are totally different.. parallel <> serial for starters. Just easier to just let software do it.
troed wrote: Tue Jun 23, 2020 11:42 pm
With a CPLD on the bus it shouldn't be too hard to make it Mega ST compatible though? Then TOS would indeed support it.
Job for you then
The RTC chips are totally different.. parallel <> serial for starters. Just easier to just let software do it.
Sure, if wanting to make it Mega ST compatible the easiest way to do it would be to use the Ricoh RP5C15 chips instead of Dallas. Then the existing PAL code used in the Mega ST just needs to be handled by a CPLD on the remake board.
Part of me likes not having to use any extra boot software. OTOH I'm sure we'll do that for other reasons anyway.
After a bit of searching I found a complete package with 20V8 JED and schematics to build up a MegaST compatible RTC. I've ordered a few RP5C15 and might try to build one up on my H4. I know there's major development done in a different direction for the remake, this is just something I do for fun for myself.
The CP software definitely doesn't work though, it has to be the FGMC package.
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
