Battery backed up 8K to 16K area

[crankorgan]

I built a external battery backed up RAM 8K to 16K. I can Poke and Peek and the values stay after power down and then. Does anybody have the steps for calling up this area. A description of the Hunter boards says BASIC can be stored there. Does anybody have a test program?

Thanks in advance

John

[Moggy]

Hi John and welcome to the forum.

I am lucky enough to have both the Hunter RAM and ROM boards which came from the States complete with manual and correspondence between Paul hunter and the customer who bought them. (He ran his garden centre business with the aid of His Zeddy!!)

But more to the point I will scan the manual and post it on here as it may be of use to others, though the introduction of Sir morris' ZXpand has rendered battery boards obsolete (Thanks Charlie)

If Your design works in the same way as the Hunters not only can You store basic (the book shows how) but I also managed to store a M/C toolkit from Adelphic software in the first 4k and the Memotech Z80 assembler EPROM code in the remaining 4k.

Give Me a day or so.

Regards
Moggy

[crankorgan]

That would be great! I like writing small controller programs in basic. It kills me to switch the power off. The Tape recorder thing is not what I want. Right now I am using an emulator but that won't drive a relay!

Thanks Moggy! I live in Lancaster PA.

[Moggy]

Quicker than I thought

Right john these are the two pages applicable to Your problem.

Although it says its primary use is for merging programs I only ever used it to store and retrieve basic programs.

Sooo use a simple code poke program to poke the short sections of code starting at 8244 and ending at 8292 to Your battery board.
To use simply type or load in a program of choice, then RAND USR 8244 will dump the basic into Your board.
If You are not merging but just want to reload Your program then,NEW the Zeddy and RAND USR 8269 will bring it back AUTO-RUNNING! So Use as a direct command, IF USR 8269=0 THEN STOP
to retrieve Your program stopped.

Hope this covers what You need John.

Regards
Moggy

[crankorgan]

Thanks Moggy! Snow coming tomorrow! I will have lots of time then. At least now I have an example! I was a computer Tech for many years. I like very simple circuits. It seems the fun went out of computers when Windows came along.

[Moggy]

Thanks Moggy! Snow coming tomorrow! I will have lots of time then. At least now I have an example! I was a computer Tech for many years. I like very simple circuits. It seems the fun went out of computers when Windows came along.

You won't get an argument from Me there john!
There are many knowledgeable people here ( I am the dullest ) who are only too willing to help and share their efforts with the zeddy fraternity.

Have fun.
Regards
Moggy.

[crankorgan]

I tried moving 10 PRINT "TEST" up and back. It went somewhere! I might have to put 10 PRINT "TEST" on a milk carton.

[crankorgan]

I just put in the two programs using POKE. I am now checking each location using PEEK. It seems to be all there after shutting down the supply.

[siggi]

Hi John,
do you know Wilf's site:

http://www.user.dccnet.com/wrigter/

Especially his RAMDOS could be useful for you:

http://www.user.dccnet.com/wrigter/inde ... RAMDOS.htm

It is a small (512 Byte) program to store and load programs to/from ramdisk. You could store the program in your ram card and use the rest (7,5 kB) as "ramdisk". Or you could add more ram (paged) to your Zeddy to have a bigger ramdisk (i have a 512 kB ramdisk in my web-server ZX81, paged in 16KB blocks from 48 to 64K).

Siggi

[siggi]

... though the introduction of Sir morris' ZXpand has rendered battery boards obsolete

Hmm, my web-server boots from battery ram. I still need it

Siggi