The Newbrain Forum

chema · 11-04-2021 19:21:57

Hi all.

I hope everyone are well in these pandemic times.

Questions about ROM version 2.0

- Alwais is possible to update from 1.91 to 2.0?.

- What advantages does it bring compared to v. 1.91?.

- Is it only necessary to change the EPROM ROM2 (A000h-BFFFh) or anhoter one also?.

- The correct md5 of A000h-BFFFh ROM is: E7E81A51E3B336EB7D7F55123949E877 ?.

My NewBrain resurected in 2011 is: Model AD UK, 32KBytes RAM, ROM 1.91, s/n 619161 /GDS.

Best regards, thanks in advance.

Chema

kluder · 13-04-2021 00:32:28

Hi
You should be able to change the ROM version, but you must change all EProm except Char EProm pos 453.

Greetings
Klaus

use google to translate

cdesp · 14-04-2021 17:07:10

The Roms that change in each version are the AB and the EF the CD is always the same.
Depending on the Machine you have those could be in seperate Eproms or all together.
In the emulator when you select version 2.0 rom the following files are used:
SERIES2.A#B
cd.rom
SERIES2.E#F

Hope this helps.

portretro · 08-07-2022 00:22:15

Hello,

You refer to ROMs AB, CD, EF ... how does this relate to 406, 407, 408?

By AB do you mean the OS/graphics routines in A000 to BFFF? And similarly, CD is BASIC and EF are the I/O and maths routines?

As 408 is a 16KB ROM, which two 8KB images go in that one? I'm guessing CD & EF.

Chema mentions ROM2 is AB ... so ROM2 == 406 as per Klaus's (I think) re-drawing?

https://newbrainemu.eu/components/com_a … -Board.pdf

There's contradictory advice: you must change all (except char. ROM) but also that only AB & EF need to be changed (CD remains the same).

Do the ROM/EPROM links need to be changed if I replace the ROM in 406 with an EPROM?

Also, there was no answer to why one would one to upgrade to version 2.00 - what's the benefit?

I managed to get my Model AD to boot last night, now to fix screen garbage ...
https://youtu.be/fnzsDMvMMXY

Thanks!!

Brett.

portretro · 08-07-2022 01:06:11

Ah huh, found some of the answers in the service manual:

406 = AB
407 = CD
408 = EF

If 407 is empty and 408 is an NEC D23128C (16KB) then it combines CD and EF.

/Brett

The Newbrain Forum

#1 11-04-2021 19:21:57

About ROM version 2.0

#2 13-04-2021 00:32:28

Re: About ROM version 2.0

#3 14-04-2021 17:07:10

Re: About ROM version 2.0

#4 08-07-2022 00:22:15

Re: About ROM version 2.0

#5 08-07-2022 01:06:11

Re: About ROM version 2.0

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