Sinclair BASIC keyword comparison
All the Sinclair machines share many common keywords, most of these are similar but there are also many differences and peculiarities such as non-standard spelling between platforms. Take the Spectrum RANDOMIZE for example, on the ZX80 this was originally spelled in British-English as RANDOMISE, which shortened to RAND on the ZX81, before becoming RANDOMIZE on the Spectrum. The Sinclair QL returned to the British-English spelling of RANDOMISE. Other differences are the array dimension base, program structure, and character codes.
The list below compares ZX Spectrum (16K) BASIC with the five other major releases of Sinclair BASIC. The relevant page can be accessed by clicking on the appropriate banner.
The current progress of Commands, Statements, et cetera, is displayed beneath each summary. The keyword lists include both those of the ZX Spectrum and the relevant Sinclair machine to which it is compared. Some keywords may count twice, such as USR, as it has more than one function.
Some keywords with the same function but which vary in the way they are spelt, such as GOTO and GO TO are counted as the same keyword, as are ASC and CODE which are different keywords with the same function. The mathematical operators ↑ and ** which both mean raise to the power of are also classed as the same. On this website Operators and Delimeters are counted as keywords.
Some keyword entries have been combined for clarity i.e. the QL keywords PENUP and PENDOWN. Not all keywords are listed as they may not have any relevance to the Sinclair machine being compared with the Spectrum, such as the Microdrive commands on the ZX80 or ZX81 pages since neither microcomputer has Microdrive capability.
The list below compares ZX Spectrum (16K) BASIC with the five other major releases of Sinclair BASIC. The relevant page can be accessed by clicking on the appropriate banner.
The current progress of Commands, Statements, et cetera, is displayed beneath each summary. The keyword lists include both those of the ZX Spectrum and the relevant Sinclair machine to which it is compared. Some keywords may count twice, such as USR, as it has more than one function.
Some keywords with the same function but which vary in the way they are spelt, such as GOTO and GO TO are counted as the same keyword, as are ASC and CODE which are different keywords with the same function. The mathematical operators ↑ and ** which both mean raise to the power of are also classed as the same. On this website Operators and Delimeters are counted as keywords.
Some keyword entries have been combined for clarity i.e. the QL keywords PENUP and PENDOWN. Not all keywords are listed as they may not have any relevance to the Sinclair machine being compared with the Spectrum, such as the Microdrive commands on the ZX80 or ZX81 pages since neither microcomputer has Microdrive capability.
ZX80 BASIC
The ZX80 was the first Sinclair computer to use a BASIC interpreter. It had integer only arithmetic and limted string handling abilities, but this little computer laid the foundations for what was to become the Sinclair ZX Spectrum.
See also: Sinclair Tape Statements, ZX Spectrum to ZX80 conversion routines 10 Commands, 34 Statements, 2 Compound Statements, 30 Functions, 17 Operators, 7 Delimiters
Last revision : 22/02/2023
ZX81 BASIC
The ZX81 improved on the ZX80 with floating-point arithmetic, trigonometric function, multi-dimension arrays, and a true string slicing facility.
See also: Sinclair Tape Statements
9 Commands, 38 Statements, 2 Compound Statements, 29 Functions, 17 Operators, 8 Delimiters
Last revision : 24/05/2023
Timex Sinclair 2068 BASIC
The US version of the Spectrum had a joystick port, ROM slot, and a 3 channel sound generator, extra keywords were added to allow use for these.
2 Commands, 2 Statements, 2 Functions
Last revision : 01/10/2023
128K BASIC
Carrying on from the original ZX Spectrum design the +128K model included an RS232/MIDI port, 2 joystick ports, 'silicon disc', and 3 channel sound generator. Not only were extra keywords added to the 128K, some commands had a slight change of syntax to allow for 'silicon disc' commands. The Amstrad marketed +2 was pretty much the same as the first 128K but the Amstrad +3 model added further keywords for the printer interface and disc drive which were added. Many of these keywords were already in use on the original Spectrum but the meanings had been changed.
12 Commands, 1 Statement
Last revision : 16/01/2024
Sinclair QL SuperBASIC
Sinclair BASIC was revamped for the QL becoming SuperBASIC. This was a structured BASIC allowing for procedures, REPEAT loops, and SELECT conditions. The QL also had Microdrives, but these were incompatible with the Spectrum's and used different commands to access and control them.
7 Commands, 57 Statements, 5 Compound or Structured Statements, 39 Functions, 26 Operators, 9 Delimiters
Last revision : 20/03/2023
This page, last revision : 03/07/2024