help revive scorpio — ZXNet «real.speccy»

From bi...@wec.ru To All 8 March 2002

People, subject!
The Scorpio ZS256 Turbo+ has broken down (I think that’s what it’s called correctly..)
The symptoms are: after turning on - a dark screen, the reset does not help...
The most interesting thing is that if you insert the ROM from ATM-Turbo2, the computer boots into
Basic 48 and works normally. True, with Randomize Usr 15616 TRDOS does not load - vertical stripes appear, as if there is no ROM at all.
At least tell me - when loading, does it test something on the board? (it may have burned out....:( )
Yes, I forgot... I already changed the ROM - with the new one everything is exactly the same. I pulled out VG93 and AY from
panels - it doesn’t help.

From Vassili Klimov To All 8 March 2002

You should first introduce yourself, sir;).

b> The Scorpio ZS256 Turbo+ has broken down (I think that’s what it’s called correctly..)
b> The symptoms are: after turning on - a dark screen, the reset does not help...
b> The most interesting thing is that if you insert the ROM from ATM-Turbo2, the computer boots into
b> Basic 48 and works normally. True, with Randomize Usr 15616 TRDOS does not
what does it mean to load into basic48? does it fall out there after a reset?

b> loads - vertical stripes appear, as if there is no ROM at all.
b> At least tell me - when loading, does it test something on
b> the board? (it may have burned out....:( )
b> Yes, I forgot... I already changed the ROM - with the new one everything is exactly the same. I pulled out the VG93 and AY from
b> panels - it doesn’t help.
either the order of the bass and trdos inside the ROM is not the same, or the interceptor
#3dxx does not work correctly. It’s possible with 1ffd something else.

JTN/4D

From Kirill Frolov To All 8 March 2002

b> boots into Basic 48 and works fine. True, with Randomize Usr
b> 15616 TRDOS does not load - vertical stripes appear, as if
b> There is no ROM at all. At least tell me - when loading, does it test anything
b> on the board? (it may have burned out....:( ) Yes, I forgot... I already changed the ROM
b> - with the new one everything is exactly the same. I pulled VG93 and AY out of the panels -
b> does not help.

Plug back the ROM from the scorpion, just connect the legs A14 and A15 so that
in any case, BASIC-48 is selected. RANDOMIZE USR 0. CLEAR 65535 -- nothing
should hang, otherwise the memory is broken. Do CLEAR 24570. POKE 24571, 0 :
POKE 24572, 201 : PRINT USR 24570. Stuck - problems with reading COPs from RAM,
broken alter, RAM, see diagram. Connect A15 back to the circuit. RESET.
If the BASIC does not appear, there is a problem with A15, look at the diagram... Try to write 01 and 02 in 1ffd
- it doesn’t hang, then the problem is here. Try to go to tr-dos.
It doesn’t work - tr-dos decoder and ROM. If it goes to tr-dos, run
memory test. memory is ok, look at the work of 7ffd bit 3, write to echo.
Just first pull out the ROM and check for vertical stripes on the screen.
The entire screen should be written in bytes 0x38 and 00. When working with BASIC, any
error should lead to freezes.

From bi...@wec.ru To All 9 March 2002

After this it really resets and hangs.
It looks like the COPs from RAM really can’t be read.
I looked at the alter’s outputs - there’s something everywhere. But this, of course, doesn’t mean anything.. I tried to turn on the turbo (for a more complete
check of the alter) - nothing changes
The logic of forming RAMM1 from M1- and RAM- also seems to work.
How can I determine more precisely?

PS. you probably won’t find altera anywhere now