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Re: SAM Coupé на ZX Evo

PostPosted: 28 Sep 2010, 17:47
Yes. Sam Coupe is very cool ZX compatible computer. But compatible only with ZX48kB. Extended memory use 32kB ram paging instead 16kB paging on ZX128/Pentagons. After connect 1MB ram can SAM COUPE use also 16kB ram paging similar as ZX128/Pentagons. More info here:

All existing software for ZX48 can be recoloured with new colour palette, can run at similar speed as ZX or at 6MHz turbo. Interrupt position is reprogrammable, can be set on screen line 0-191 (191 = similar as on Pentagon, at end of screen).

SAA1099 sundchip are used also on russian ZXM SOUNDCARD and use compatible ports with SAM:

Graphic mode is 1 is compatible with ZX and full 512kB ram can be used as 32 videorams. Graphic mode 2 is hardware multicolor with linear screen data. Mode 3 is hi-res color mode and mode 4 is ZX mode without attributes (color pixels). Each pixel can use one from 16 colours with palette. Data are linear (24kB for one screen). Ram 512kB can contain up to 16 videorams in this mode.

FDD is based on VL1772 (controller used on ATARI ST or +D/DISCIPLE for ZX. SAM COUPE basic is based on MASTER BASIC for ZX Spectrum.

Re: SAM Coupé на ZX Evo

PostPosted: 09 Dec 2010, 22:40
by acidrain
this would be great to have sam on pentevo, even if one slot of zx-bus will be used for saa sound card i believe

Re: SAM Coupé на ZX Evo

PostPosted: 17 Dec 2010, 01:51
TS-Labs wrote:I don't think that it could be possible to emulate SC on Pentevo. Sad, but true...

EVO can't use full 128 colour palette then need graphic card with SAM COUPE graphic modes.
Next way is redesign EVO board for possibility use more colours.

SAA1099 sound chip can be emulated or use real ZXM SOUND card (or add SAA1099 to SAM COUPE graphic card)

VL1772 can be emulated or unused. Exist ATOM HDD interface with B-DOS support for use FDD images on HDD.

Re: SAM Coupé на ZX Evo

PostPosted: 17 Dec 2010, 23:12
TS-Labs wrote:čím to může být emulovane? zvukový čip ještě ano, ale VL1772! možnosti Altery vobec není dost pro toto. a co o frekvenci 6 MHz? Pro mne, těžké je to udělat.

We don't need emulate VL1772 at low level. Only use modified DOS with IDE support. This DOS is signed as "B-DOS" and use FDD drive 2 as MGT image on HDD.
More info about ATOM HDD here: ... e/atom.htm

About 6MHz :
main oscillator speed can be 48 MHz
48 MHz / 8 = 6 MHz pixel clock
48 MHz / 6 = 8 MHz for SAA1099 clock
48 MHz / 27 = 1.77 MHz (for AY-3-8912 or YM2149)

Re: SAM Coupé на ZX Evo

PostPosted: 19 Dec 2010, 18:57
TS-Labs wrote:Thanks for info.
The problem is that FPGA wouldn't success at 48 MHz. I discussed this question before with LVD and made my own tests, so 28 MHz is the only choice as yet.
To make it work at 48 one should thoroughly rewrite the Verilog sources to fit all timings.
It is possible, but needs too much efforts.

Then will possible use 28MHz as main CLK:
14MHz as pixel clock
7MHz for CPU (and 3.5MHz if ZX mode is set)
1.75 MHz for AY (if will used)
screen niming will different and some software run about 17% faster.
SAA1099 can be on external sound card with 8MHz oscillator, or emulated in FPGA and clock must be calculated from 28MHz (28 MHz / 3.5 = 8MHz).
SAM COUPE software use programmable INTerrupt timing on any screen line 0-191, only demos with perfect timing will work at high speed...

Emulation of other SAM's features is not hard.
SAM MOUSE - return relative positions X,Y and buttons state.
MIDI CONNECTORS/PORTS - can be ignored, not exist good software for it
EXTERNAL MEMORY 1MB - canbe emulated, EVO contain 4MB ram (512kB for SAM COUPE and 1MB for EXTER.MEM). Sam support up to 4MB external memory, then on EVO can be used 3x 1MB module :-)
FDD - fdc controller VL1772 can be ignored and all FDD operaions will redirect to HDD via B-DOS (need only sam coupe IDE ports)
RTC 72421 - don't need, but can be emulated on EVO
graphic modes - hires 512x192/4colours + 256x192/16colours pex pixel + 256x192/hardware multicolor mode with 8x1 attributes + 256x192 ZX mode (in all this modes is used colour palette and all other modes than ZX mode use linear data layout in memory)
memory paging - easy 32kB paging with 16kB shifting. Enable set allram mode, active write protect in low 16kB(in allram mode for better rom emulation). Rom size is only 32kB (first 16kB can be connect only in low 16kB and second 16kB only from 49152. High 32kB of adress space can be disabled for enable connect 1MB external memory. This memory is connect from 32768-65535 and use two paging ports for 16kB paging from adress 32768 and 49152 (similar as on ZX128/Pentagon)
colour palette - 128 colours = 2xred + 2xgreen + 2xblue + 1xbright. On EVO must be BRIGHT bit ignored or implement on external graphic card.
keyboard - sam coupe use 100% compatible keyboard layout and ports with ZX Spectrum 48(two layers membrane) + next extra keys on new ports
ZX compatibility - original SAM can active ZX graphic mode and CPU will slow down from 6MHz to similar speed as ZX (only about 20% faster than ZX). If in EVO will use 28MHz oscillator then in ZX mode can SAM COUPE run at 3.5MHz (or at 7MHz if will implement turbo CPU mode)
SAM JOYSTICK - on SAM COUPE is one joystick port with possibility connect joystick splitter for connection SINCLAIR 1 and SINCLAIR 2 joysticks (keys 1-5 and 6-0 as on ZX). Some SAM's software use this joystick controll.

Kempston mouse - can be emulated for possibility use on SAM COUPE in ZX mode :-)
System bus on EVO - no problem...
NEMO IDE - can be implement also, no problem
TR-DOS - can be implement (must be enable on any extra port if ZX mode is set...
Pentagon 1024 compatibility - port 7FFD can be used if ZX mode is set (need extra port for enable it)
Kempston joystick - this port is not used on SAM COUPE software, but in ZX mode can be used for controll in ZX software/games

With all this features will EVO board compatible with SAM COUPE and Pentagon 1024. It's very good idea. After power on can be automatically active ZX mode (Pentagon 1024 with tr-dos)....

Re: SAM Coupé на ZX Evo

PostPosted: 20 Dec 2010, 03:57
TS-Labs wrote:I'm afraid that on 7MHz all demo effects will spread.
If there are some multicolors in demos, we'll need to make CPU stall 64 tacts per videoline out of 448 at 7 MHz to obtain "6MHz" mode.
It could be done by cancelling every 7th tact of CPU clock.

Can be. But SAM COUPE not use often multicolors. This computer contain hardware multicolor mode with 8x1 attributes but all SAM's software (demos/games) run in graphis mode 4 = 256x192 with colour pixels (each pixel contain one colour from 16 and colour palette is used). For good screen synchronisation are used programmable interrupt at end of any TV line. Also up to 32 videorams can be used then don't need any perfect screen timing, use vram switching as on ZX128. Amiga MOD players and samplers will work faster...

Re: SAM Coupé на ZX Evo

PostPosted: 20 Dec 2010, 19:21
TS-Labs wrote:It uses. And I mean border effects.

Yes, only border effects (text in border). But exist only small part of software... (demos) ... re=related

TS-Labs wrote:What players? ... re=related
Exist more players... I don't know name... :-(

Re: SAM Coupé на ZX Evo

PostPosted: 20 Dec 2010, 23:27
TS-Labs wrote:Wow. And on what hardware are those played?
D'you know, that 6MHz (in fact, much less: ~4MHz on SC) is FAR not enough, even if you have DAC-DMA, as SEGA 4xmpl does?

This player can use SAA1099 soundchip(low quality) or D/A convertors ( high-quality -> )
SAM COUPE use 6MHz CLK for CPU, but ULA slowdown CPU via WAIT to speed about 4.8 MHz. But if 1MB memory is connect in high 32kB of adress space then memory area 32768-65535 run always at 6.0 MHz !!!
Also all routines in ROM run at 6.0 MHz. DMA on SAM COUPE is possible connect ( ) but better is faster Z80 CPU ( Mayhem accelerator use external Z80 CPU on 24MHz )

Re: SAM Coupé на ZX Evo

PostPosted: 21 Dec 2010, 12:08
by DimkaM
нда, Гугль-хром не справился с переводом.

Re: SAM Coupé на ZX Evo

PostPosted: 21 Dec 2010, 20:10
by lvd
Нихрена не "розумим", вот.