vortex 512KB internal ram expansion - testing help needed

[arnoldemu]

Does anyone have a Vortex 512KB internal ram expansion in their CPC464?

I have made some tests and checked it on my ram expansion, but bit 3 of i/o port fbbd which enables/disables the ROM on the expansion ROM is not working as I expect.

The documentation seems to say it is a simple enable/disable, but I am seeing something different. When bit 3=0 all works as expected, but when it's 1 things are a bit strange (but consistent). My RAM expansion works perfectly otherwise and I don't know if this part of it is broken or not.

Would anyone be able to run it on their machine and tell me the results?

I can send you the dsk/cdt. Thanks!

[TFM]

Why do you think that yours is broken?


Well, I do have one in a 464 in Munich, I'll be there from May 6th to 22nd, I 'could' run a test for you in case I can set up the system and run it. The most easy way would probably be to make a DSK which I simply run and it saves its results on the disc, so I can send you a DSK back. (Or whatever works for you).

The reason for me answering 'late' is that I really don't know if I can make it in time. But nobody else did answer here.

If you already got help, then please ignore this text.

[arnoldemu]

Why do you think that yours is broken?

From English documentation:

"Bankselect FBBD (port address)"

"3  RAMexpansion: ROM disable; 0 = enable ROM, 1=disable ROM"

"bit 3 and 4 are reserved for special applications and will crash the system if not properly used"

I don't see German documentation here, perhaps it has some extra information?

I thought I write 1 to bit 3 then ROM on vortex pcb is disabled.  But when I do that I see this rom at &0000-&3fff and &c000-&ffff in some conditions. I don't know if this is the same for all or a bug on mine

All the other bits work as expected.

[TFM]

Ok, just have a DSK ready until May 3rd, I can run it on the 464 with Vortex expansion (if I get a floppy connected, but this should be doable somehow).



EDIT: What does 'disabled' mean here?


1. To disable the ROM and bank RAM in? (Probably not, because &7Fxx is used to enable/disable ROM)


2. To disable the Vortex-RAM and enable another external ROM at the same position? (Is it that what they mean).




Maybe the sentence is misleading? 

[arnoldemu]

Ok, just have a DSK ready until May 3rd, I can run it on the 464 with Vortex expansion (if I get a floppy connected, but this should be doable somehow).

Ok I will.
Thanks.

Do you have time to test inicron ram too?

EDIT: What does 'disabled' mean here?


1. To disable the ROM and bank RAM in? (Probably not, because &7Fxx is used to enable/disable ROM)


2. To disable the Vortex-RAM and enable another external ROM at the same position? (Is it that what they mean)

Maybe the sentence is misleading? 

This is what I thought:

Code Select Expand


;; disable ROM on vortex ram pcb
ld a,%1000
ld bc,&fbbd
out (c),a
;; enable upper rom
ld bc,&7f00+%10000100
out (c),c
;; select rom 6
ld bc,&df06
out (c),c
ld a,(&c000)
;; here I expect NOT to read vortex ROM but another (e.g. BASIC or a ROM
;; on a romboard depending on what roms are installed and the hardware used)


Code Select Expand


;; enable ROM on vortex ram pcb
ld a,%0000
ld bc,&fbbd
out (c),a
;; enable upper rom
ld bc,&7f00+%10000100
out (c),c
;; select rom 6
ld bc,&df06
out (c),c
ld a,(&c000)
;; here I expect to read vortex ROM. (assume no external roms and vortex rom overrides internal rom)


Code Select Expand


;; enable ROM on vortex ram pcb
ld a,%0000
ld bc,&fbbd
out (c),a
;; enable upper rom
ld bc,&7f00+%10000100
out (c),c
;; select rom 0
ld bc,&df00
out (c),c
ld a,(&c000)
;; here I expect to read ROM 0 (not vortex ROM)


But it does different!

Code Select Expand


;; disable ROM on vortex ram pcb
ld a,%1000
ld bc,&fbbd
out (c),a
;; enable upper rom
ld bc,&7f00+%10000100
out (c),c
;; select rom 6
ld bc,&df06
out (c),c
ld a,(&c000)
;; I see vortex ROM data! It is not disabled!


[TFM]

Do you have time to test inicron ram too?

No problem at all! Since this setup it active and running anyway. It's at the 6128 Plus I have and switched to internal 128 KB. (As you know the 512 KB RAM expansion allows to select the 2nd 64 KB from the 128 KB or the RAM expansion when having a 128 KB machine. You can tell me which option you prefer, or I test just with both options). Again: Just make a DSK for me before May 3rd or so. 


EDIT: If you don't make it in time, then post it here before May 20.