Wanted: ICD RAMBO XL Schematic

[ClausB]

21 hours ago, TZJB said:

Thank you for the suggestion of your RAMdisk driver. I have the one that comes with Sys-Check 2.2 for MyDOS, is that it?

I don't know. Here's the source. It patches the OS, not DOS, so it emulates a drive on the sector level.

qmegxld.zip

[TZJB]

21 hours ago, reifsnyderb said:

The top shielding probably won't fit as it's way too close.

 

I've done something similar by adapting my 320k PBI upgrade to an internal upgrade except I do it with the CPU.  Also, I have a special board made for the 74LS08 chip so that PBI /EXTSEL still disables the internal RAM.  In this picture you can also see the DRAM chips are removed.  The OS and BASIC changes are visible as well as the S-Video conversion.

 

That looks a pretty neat solution and you can probably fit the top shield too! With my THFF 512K expanded 800XL, I have just put all the screws back in with 4mm washers instead of the top shield in order to hold the bottom shield, and to stop the screws protruding from the case. It works well.

 

21 hours ago, reifsnyderb said:

OS V4 works great on the XLs.  If I have a 320k memory upgrade installed, the self test shows some of the extra memory as bars in the lower part of the screen.  

 

 

This is on a 320k 600XL with OS V4.

 

 

This looks good too. Regarding OS4. Do you actually need a seperate BASIC ROM if it is built into the OS?

Edited October 25, 2022 by TZJB

[TZJB]

1 hour ago, ClausB said:

I don't know. Here's the source. It patches the OS, not DOS, so it emulates a drive on the sector level.

qmegxld.zip 2.77 kB · 1 download

Thanks Claus. I am really no good with Assembler though and just rely on other people to produce a guide of what is needed. What version of OS does it patch out of curiosity as I have just discovered OS V4!?

Edited October 25, 2022 by TZJB

[reifsnyderb]

9 minutes ago, TZJB said:

That looks a pretty neat solution and you can probably fit the top shield too! With my THFF 512K expanded 800XL, I have just put all the screws back in with 4mm washers instead of the top shield in order to hold the bottom shield, and to stop the screws protruding from the case. It works well.

I wasn't able to re-install the top shield, unfortunately.  There isn't much space.  But I did install the bottom shield in a similar manner.

 

9 minutes ago, TZJB said:

 

This looks good too. Regarding OS4. Do you actually need a seperate BASIC ROM if it is built into the OS?

 

The BASIC ROM isn't built into the OS and is a separate chip.  It is nice having Rev. C installed, though.

 

[TZJB]

21 hours ago, kheller2 said:

I completely understand there are much better ways to upgrade a 600XL.  But as long as we are doing old school upgrades, I was curious if anyone back then had modified a RAMBO for a 600XL.

The traditional Atari 600XL upgrade has always been PBI, even for 64K. I don't believe that there was ever a traditional way to perform an internal RAM upgrade beyond 64K due to lack of sockets/space although it may be possible with a 256K SIMM I guess.

[ClausB]

2 hours ago, TZJB said:

What version of OS does it patch out of curiosity as I have just discovered OS V4!?

It patches whatever OS is in ROM after copying it to the underlying RAM. It overwrites the international character set at CC00.

[TZJB]

2 minutes ago, ClausB said:

It patches whatever OS is in ROM after copying it to the underlying RAM. It overwrites the international character set at CC00.

I think I understand. It patches the OS in RAM and creates a new virtual disk drive in the Rambo XL memory. You probably already know what I am going to ask now. Do you have a copy of the executable please?

[reifsnyderb]

Maybe I am misunderstanding.  But if the reference was to the OS V. 4 I am using, I am using the OS from the XEGS and installing it on a 600XL.  BASIC is on a separate chip.  Missile Command isn't included.  It's really the newest XL/XE operating system burned onto an EPROM.  

[TZJB]

3 hours ago, reifsnyderb said:

Maybe I am misunderstanding.  But if the reference was to the OS V. 4 I am using, I am using the OS from the XEGS and installing it on a 600XL.  BASIC is on a separate chip.  Missile Command isn't included.  It's really the newest XL/XE operating system burned onto an EPROM.  

I understand that you are using the OS V4 from the XEGS, however OS V4 is 32K containing 16K OS, 8K Missile Command and 8K Basic. That's why it needs your 256K EEPROM chip. Atari OS V1-3 are 16K and fit a 128K EPROM. I wondered if you could switch to the OS V4 BASIC or even Missile Command. I don't have a XEGS so I am not sure of the switching arrangments. I will have to try it, it sounds like fun.

[ClausB]

4 hours ago, reifsnyderb said:

I am using the OS from the XEGS and installing it on a 600XL.    It's really the newest XL/XE operating system burned onto an EPROM.  

If it doesn't have the alternate character set at CC00 then my driver won't work.

[ClausB]

5 hours ago, TZJB said:

Do you have a copy of the executable please?

I can build you one when I get home Friday. Single or double density? Which drive numbers?

[reifsnyderb]

2 hours ago, TZJB said:

I understand that you are using the OS V4 from the XEGS, however OS V4 is 32K containing 16K OS, 8K Missile Command and 8K Basic. That's why it needs your 256K EEPROM chip. Atari OS V1-3 are 16K and fit a 128K EPROM. I wondered if you could switch to the OS V4 BASIC or even Missile Command. I don't have a XEGS so I am not sure of the switching arrangments. I will have to try it, it sounds like fun.

Ok.  I get it now.  I am using OS V4 in a 600XL so it's not setup for Missile Command and I am just using 16k of the chip.  The 8k BASIC is also in a separate chip.

[TZJB]

20 hours ago, ClausB said:

I can build you one when I get home Friday. Single or double density? Which drive numbers?

Thanks Claus, that's very kind. I realise from your question that the built executable is very specific as to drive number and density and that is the reason you originally sent the assembler code. So if I am only choosing one, single density D4: please.

[TZJB]

20 hours ago, reifsnyderb said:

Ok.  I get it now.  I am using OS V4 in a 600XL so it's not setup for Missile Command and I am just using 16k of the chip.  The 8k BASIC is also in a separate chip.

Aye, thanks for your suggestion. I have just tried the XEGS OS V4 ROM from the Nir Dary CDs in my 800XL with pretend Rambo XL, as featured previously. As you said, the 32K OS V4 ROM is defaulting to the 16K OS with the BASIC and Missile Command unaccessible. I tried the memory test and was a bit worried when the expanded memory test started as it took so long for the first bank to complete, but then I remembered it is a 16K bank and not 1K like the main memory. The test eventually completed successfully and showed the extra four 16K banks of a 130XE like yours did, so the built in memory test works fine. Nir Dary has also individualised the V4 OS ROM so it would be possible to just use a 128K ROM for the OS alone. I shan't bother as I have loads of 27256 chips to play with. I would like to try the @ClausB RAMdisk with OS V4 now and I am guessing it should work.

[+kheller2]

On 10/25/2022 at 6:24 PM, TZJB said:

I understand that you are using the OS V4 from the XEGS, however OS V4 is 32K containing 16K OS, 8K Missile Command and 8K Basic. That's why it needs your 256K EEPROM chip. Atari OS V1-3 are 16K and fit a 128K EPROM. I wondered if you could switch to the OS V4 BASIC or even Missile Command. I don't have a XEGS so I am not sure of the switching arrangments. I will have to try it, it sounds like fun.

Let’s be clear.  All the XL/XE OS versions are 16k.  In the case of the XEGS one ROM chip contains the OS, BASIC and a game. In the case of a 1200XL the OS is split over two 8K chips. I’m not sure you could put the XEGS chip in another board (maybe you could if the OS was the first part of the chip) but you wouldn’t be able to access BASIC or the game without additional support circuits. 
 

Also remember that while v4 detects additional RAM it can’t properly test it due to bugs. 

[TZJB]

8 hours ago, kheller2 said:

Let’s be clear.  All the XL/XE OS versions are 16k.  In the case of the XEGS one ROM chip contains the OS, BASIC and a game. In the case of a 1200XL the OS is split over two 8K chips. I’m not sure you could put the XEGS chip in another board (maybe you could if the OS was the first part of the chip) but you wouldn’t be able to access BASIC or the game without additional support circuits. 
 

Also remember that while v4 detects additional RAM it can’t properly test it due to bugs. 

I partly agree. However I think that it has been proven that the OS V4 works in any XL/XE as the OS sits in the last part of the 256K ROM. With A14, Pin 27 of the 256K ROM fixed to a high state, the high 16K OS bank is always selected. I do also recall that the last two 16K banks of the extended memory test only re-test the first two banks due to the bug you mentioned. Wasn't there a fix for that?

These are the notes from Nir Dary to clarify:-

xem65os.rom      same as the complete XEGS ROM
                       first  8k : missile command
                       second 8k : BASIC rev.C
                       final 16k : XL/XE OS rev.4

 

[ClausB]

On 10/26/2022 at 3:43 PM, TZJB said:

single density D4: please.

Load and run this:

 

QMEGXLS4.OBJ

[TZJB]

On 10/28/2022 at 5:13 PM, ClausB said:

Load and run this:

 

QMEGXLS4.OBJ 593 B · 2 downloads

Thanks Claus. Much appreciated. I just need to work out how to get this from my PC to my Atari. Anyone know a quick method please?

[ClausB]

On 10/31/2022 at 8:01 AM, TZJB said:

I just need to work out how to get this from my PC to my Atari.

You need SIO2PC or SIO2USB or FujiNet or SIO2SD.

[+kheller2]

Or a null modem cable and some terminal software.

[TZJB]

4 hours ago, ClausB said:

You need SIO2PC or SIO2USB or FujiNet or SIO2SD.

 

1 hour ago, kheller2 said:

Or a null modem cable and some terminal software.

Thanks for your suggestions guys, I do have a Fujinet, however I found a quick way that I didn't know existed. Move QMEGXLS4.OBJ to a folder on the PC. Run Altirra and mount D1: with DOS2.0s, then the folder with QMEGXLS4.OBJ as D2:. Boot into DOS and from there QMEGXLS4.OBJ can be copied from D2: to an existing or new mounted ATR disk image.

Incidentally, I must be doing something wrong because I can't get DOS to see D4:, which should be the RAMdisk after I run QMEGXLS4.OBJ. I tried it in Altirra emulating a 256K RamboXL utilising Altirra OS and Atari OS V.3, and my 800XL RamboXL with OS V.3 and OS V.4. Both with DOS2.0s. How should the RAMdisk operate please? Has anyone tried it?

[ClausB]

1 hour ago, TZJB said:

I can't get DOS to see D4:

It's been a while but I think DOS by default will only look for D1 and D2. You have to POKE something and rewrite the DOS files to make it see D3 and D4, IIRC. Then format D4.

[ClausB]

https://forums.atariage.com/topic/259893-atari-dos-20-disk-drives/?do=findComment&comment=4679021

[+kheller2]

Under DOS 2.5 there is a setup/configuration utility you can run that will configured the amount of drives/buffers and ram disks.

[mutterminder]

On 5/13/2022 at 11:02 AM, ClausB said:

You're welcome.

 

I worked for them and didn't know it. I put my design into public domain and they produced it.

Thanks for making that design.  Years ago, I installed it in an 800 XL with piggybacked chips and point to point wiring. It worked great!