Spectrum Next

Overview

The BeebFpga project now includes two cores for the Spectrum Next:

a BBC Micro (Model B) core, using the cycle accurate T65 6502 implementation
a BBC Master core, using Alan Daly's 65C02 implementation

These cores include a common set of features:

High quality VGA output @ 50Hz
Original sRGB SCART output @ 50Hz
Membrane Keyboard support
Beeb SID support
Music 5000 support
Internal 4MHz 65C02 Co Processor (for Tube Elite!)
VideoNuLA (an extended colour palette and additional screen modes)
MMFS SD Card File System

There are further features in develoment that are currently disabled in this release:

an ICE 6502/65C02 debugger (uses the ESP Wiki connector as a 115,200 baud serial port)
an external Pi Tube Direct Co Processor (uses the Pi Accelerator connector)

These are disabled because of possibile compatability issues with the normal use of the Spectrum Next Wifi Module and Pi Accelerator.

Known Issues

The PS/2 Keyboard does not work in this release

Installation

The latest version of the Spectrum Next BeebFpga cores can be found here: https://github.com/hoglet67/BeebFpga/releases/latest

It contains the following files:

./cores/AcornMaster/adfs.rom
./cores/AcornMaster/bbc_master_spec_next.bit
./cores/AcornMaster/boot.ssd
./cores/AcornMaster/dfs.rom
./cores/AcornMaster/edit.rom
./cores/AcornMaster/launch.bas
./cores/AcornMaster/owl.rom
./cores/AcornMaster/view.rom
./cores/AcornMaster/viewsht.rom
./cores/AcornModelB/bbc_micro_spec_next.bit

These should be copied onto your Spec Next SD Card.

Follow the normal process to install the core as your extra core:

copy the appropriate core .bit file to the SD card root directory, and rename it to CORE001.bit
hard reset the Spectrum Next while holding down the C key to launch the Extra Core Updater
press Y to write the extra core to FLASH
hard reset the Spectrum Next
from the Spectrum Basic command line, type reg 16,255 to switch to extra core

ROMs

Both the BBC Micro (Model B) and BBC Master Cores contain 64KB of ROM data in the .bit file. This is sufficient to provide a runnable system (i.e. OS, Basic and a SD File System). So if all you want to do is to play games, you don't need any additional ROMs.

In the case if the BBC Master Core, several standard ROMs (DFS, ADFS, Edit, View and View Sheet) are omitted, as is the Owl Logo ROM. There is a ROM loader Basic program provided in /Cores/AcornMaster/launch.bas that will pre-load these missing ROM images into memory (at the right banks), then switch to the core. Running this program is a convenient way to start a complete BBC Master system.

MMFS SD Card File System

MMFS is a modern SD Card File System, widely used in the Acorn community, and is included as standard in the Beeb FPGA Cores. MMFS uses a FAT16/32 formatted SD Card containing a single file called BEEB.MMB. This file is normally ~100MB, and is a concatenation of 511 raw 200KB 80-track disc images.

There are two limitations with MMFS's use of the SD Card:

BEEB.MMB must be one of the first 16 files in the root directory
BEEB.MMB must be contiguous (i.e. it cannot be fragmented)

For these reasons, it's recommended that you use a seperate SD card for MMFS.

However, it is possible to build a SD card that contains both MMFS's BEEB.MMB file, and the Spec Next distribution, by following these steps:

start with freshly formatted SD Card (FAT16 or FAT32)
copy the BEEB.MMB file to the SD Card
copy the Spec Next distribution files to the SD Card
copy the BeebFpga additional core files to the SD Card

Here is a link to a standard BEEB.MMB file: https://github.com/hoglet67/BeebFpga/releases/download/specnext_beta1/BEEB.MMB.zip

It contains the following

Disk 0: Stairway to Hell Archive MENU
Disk 1: Beeb FPGA Support Disk
Disk 2: MMFS 1.44 ROM images
Disk 3: Klaus Dormann 6502 Test Suite
Disk 4: Bruce Clark BCD Test Suite
Disks 20-252: Stairway to Hell Archive Disks
Disk 299: 6502 Co Processor Life
Disks 301-315: Beeb SID Demos
Disk 320: Music 5000 System Disk
Disks 323-352: Music 5000 Compilation Disks
Disk 360: Bad Apple
Disk 370: Video NulA System Disk
Disk 371-377: Video NulA Demo Disks (gallery, games, etc)
Disk 400-437: Retro Software Games

See the examples section below for some things to actually try out!

The complete MMFS Command Reference can be found here: https://github.com/hoglet67/MMFS/wiki/Command-Reference

Basic Operation of the Core

The buttons on the side of the Spec Next are used by the core as follows:

A short press on the Red (Reset) button will perform a power-up reset on the Beeb Core. This should recover from any possible program crash.

A long (1s) press on the Red (Reset) button will reconfigure the system back to the Spec Next core. This saves having to power cycle.

A short press on the Green (Drive) button will toggle the internal 65C02 Co Processor on/off. Initially it is off. A Control-BREAK is needed after changing this setting. (Control is mapped to the GRAPH key)

A short press on the Yellow (NMI) will cycle through four different video output modes:

Mode 0: RGB SCART Video with Composite Sync
Mode 1: VGA, using the RGBtoVGA scan doubler for all screen modes
Mode 2: VGA, using the Mist scan doubler for all screen modes
Mode 3: VGA, using the Mist scan doubler for Modes 0-6, and native VGA output for Mode 7

All of these use the VGA connector; HDMI may be supported in a future release.

The RGB SCART mode is identical to an original BBC Micro. It requires a VGA to SCART cable, and a television woth an RGB capable SCART input.

The VGA modes are all 50Hz, so your VGA monitor must support 50Hz for this to work (many don't). I personally use a HP LP2065 monitor, which is excellent. Depending on the monitor, you may need to play around with the monitor's CLOCK and PHASE settings to get a good looking image.

The default video mode when the core starts is always mode 3.

Membrane Keyboard Mapping

Mapping the 58-key Spectrum Next keyboard to 74-key BBC Micro keyboard was somewhat of a challenge.

The mapping is as follows:

Spec Next Key	Beeb Key
BREAK	BREAK
EDIT	ESCAPE
TRUE VIDEO	TAB
INV VIDEO	COPY
CAPS LOCK	CAPS LOCK
GRAPH	CTRL
CAPS SHIFT	SHIFT
EXTEND	See below
SYMBOL SHIFT	See below
DELETE	DELETE
ENTER	RETURN
Up/Down/Left/Right	Up/Down/Left/Right
A-Z	A-Z
0-9	0-9
;	; and +
"	: and *
,	, and <
.	. and >

This misses out the following Beeb keys:

@
‐ and =
^ and ~
/ and |
[ and {
] and }
_ and £
/ and ?

To access these, it's necessary to use the Spec Next SYMBOL SHIFT as a modifier, which operates exactly as it does in the Spec Next core. For example, SYMBOL SHIFT + L should give you =. i.e. just look for the key cap with the symbol character you need.

Finally, the EXTEND key is also used as a modifier to access the 10 red BBC function keys. For example, F1 is Extend + 1.

PS/2 Keyboard Mapping

The PS/2 Keyboard mapping is the same as other Beeb Fpga implementations, and attempts to map keys by physical position.

For example, the Beeb ; key is next to L, and the Beeb : key is just to the right of that.

This can be confusing at first, but it gives a better experience when playing games (most of the time!)

Examples

These instructions all assume the Master version of the Core is loaded.

Planetoids

Shift-BREAK to boot STH Menu
43
E
Enter

Rocket Raid

Shift-BREAK to boot STH Menu
47
T
Enter

Pheonix (by Tricky)

*DBOOT 436

Tube Elite

Enable the Co Processor by pressing the Green DRIVE button
Control Break (Control = GRAPH key)
*DIN 45
*TUBEELT
Press Space
Press F0 (Extend-0) to launch

The flight controls are documented here: http://www.elitehomepage.org/playguide.htm#A14

And here's a scan of the original "Space Trader's Flight Training Manual": https://openretro.org/file/37a540d376344ac9add72431ecf70ab46dfb7fe4

The Spec Next keyboard layout is not ideal for this!

Music 5000

*DBOOT 320
*DBOOT 320
Use Up/Down/Enter to select "Load program"
enter filename: ppach
Enter to "Run program"

Other music files on this disc are:

concert
pavane
ppach
jukebox

After pressing Escape, F0 (Extend-0) will return to the menu.

Beeb SID

*UNPLUG 9
Control BREAK
*DBOOT 305 ( or any disk from 301 to 315)

Provide feedback

Saved searches

Use saved searches to filter your results more quickly