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0000144Allocated to current language
007032Guaranteed unused with BASIC
009016Econet workspace
00A08Allocated to current NMI owner
00A88OS command workspace
00B016File system scratch space
00C016File system private space
00D01VDU status
Bit 0 VDU 2 enabled
Bit 1 Scroll disabled
Bit 2 Paged scroll selected
Bit 3 Soft scrolling
Bit 4 unused
Bit 5 VDU 5 enabled
Bit 6 Set when edit/text cursors are separated
Bit 7 Set if VDU driver disabled
00D11Byte mask for current graphics point
00D22Text colour to be ORed & EORed into memory respectively
00D42Graphics colour to be ORed & EORed into memory respectively
00D62Address of top line of current graphics character cell
16 Shift lock
32 Caps lock
48 No locks
00DA6Temp workspace
00E02Pointer to row multiplication table, high byte first
00E21Cassette filing system status
Bit 0 Input file open
Bit 1 Output file open
Bit 2 Unused
Bit 3 Set if currently *CAT
Bit 4 Unused
Bit 5 Unused
Bit 6 Set if at end of file
Bit 7 Set if end of file warning issued
00E31Cassette filing system options *OPT
00E43General OS workspace
00E71Auto repeat countdown timer
00E82Pointer to input buffer used by OSWORD 0x01
00EA1RS423 timeout counter
<0 RS423 system holds 6850 but has not yet timed out
=0 RS423 system holds 6850 but has timed out
=1 Cassette filing system using 6850
00EB1Cassette critical flag
00EC1Internal key no of most recently pressed key
00ED1Internal key no of first key pressed of those still pressed
00EE1Internal key number of character to be ignored when scanning keyboard
Note 0xEE is also RAM copy of 1MHz bus register
00EF1Accumulator value for most recent OSBYTE/OSWORD
00F01X register for most recent OSBYTE/OSWORD
00F11Y register value for most recent OSBYTE/OSWORD
00F22text pointer for processing OS commands/filenames
00F41RAM copy of currently selected Paged ROM
00F51Current logical speech PHROM or ROM filing system ROM number
00F62Address pointer into paged ROM or speech PHROM
00FA2General OS workspace
00FC1Accumulator saved in IRQ routine
00FD2Pointer to error message
00FF1Escape status
Bit 7 set if ESCAPE pressed

On the BBC Micro addresses 0x0000…0x008F are reserved for the current language. The table above lists the known BASIC II memory map for those addresses.

BBC Basic reserves 0x0070…0x008F for user programs. User code should not use addresses outside that range unless they have replaced BASIC.