Firmware

Public Domain

Edwin Blink

The HD BOOT ROM is for use with the ATOM hard disk interface to automatically boot B-DOS from the hard disc..

General Information:

The HD BOOT ROM is a version 3.0 Basic ROM which will boot the DOS from hard disk or floppy disk automatically when the SAM is turned on or reseted.

This ROM will also reset the SAA sound chip directly after a reset and defines the function keys F7 as DIR [RETURN] and F8 as DIR PEEK SVAR 7 [RETURN] instead of the tape commands.

Great care was taken to add these features and keep the ROM fully compatable with the original 3.0 ROM. For this reason the original copyright message had to be removed. The copyright message now will be ‘HD BOOT ROM V2’ (After NEW and DOS is already in memory).

How It Works:

When the SAM is turned on or reseted, the SAA sound chip is reseted and the normal reset procedure is continued. Holding the SHIFT key down during reset will give you a 256K SAM to work with. Before the copyright message is printed a test is made if DOS is in memory and if not it will fool basic that key F9 is pressed and the DOS is booted.

The BOOT command works in the same manner as before. But now it boots from hard disk. It is still possible to boot from floppy disk by holding down the SPACE BAR during reset or by disabling the hard disks bootsector (see below).

Making the hard disk bootable:

To make the hard disk bootable the following has to be done:

1. Blow an 32kB EPROM with the HD BOOT ROM BIN image.
   
2. Replace the SAM ROM with the HD BOOT ROM.
   
3. Make a boot record.
   
4. Initialise boot sector with the ‘MakeBoot’ program.

Installing the HD BOOT ROM

MGT

Dr Andy Wright

SAM Basic was one of the prime selling points of the machine in it’s early days, written by Dr Andy Wright and with it’s roots in the highly successful BetaBASIC for the ZX Spectrum it offered a powerful interpreter with many advanced features such as sound and sprite handling.

Information from Frode Tennebø taken from the Sam Coupé Scrapbook

Programs may be up to 217K long on a standard 256K Coupe. (470K on a 512K). Line numbers up to 61439 are allowed, with each line containing up to 127 statements. Strings and arrays can have names up to 10 character long. The names of user-defined functions and numerical variables can have up to 32 characters. Strings can be up to 64K long; arrays can fill all available memory. SAM Basic is fully structured and includes procedures with local variables and parameter passing by value and reference. Long and short IF and ELSE are implemented, as are DO, LOOP, REPEAT, UNTIL, a CASE equivalent, ON, ON ERROR and GOTO label.

Graphics are well catered for, with vary fast DRAW, CIRCLE, PLOT and pattern FILL. RECORD and BLITZ allow complex graphics sequences to be stored and replayed at high speed. Any part of the screen can be moved in any direction with ROLL and SCROLL, and sections can be GRABed and PUT back elsewhere. PALETTE allows instant changes to the screen colours; all 128 colours can be displayed at once. The displayed screen can be instantly switch for another. The character set includes block graphics and a wide range of foreign characters. Character size can be altered to give 32, 64 or 85 columns. Double-hight characters can also be used. Text and graphics screen copies can be made to a suitable printer in a variety of sizes.