This table summarises and compares the features of the Starter, Personal and Professional Editions of v9.3 Astrobe for each type of Cortex-M microcontroller.

IDE / Editor	M0	M3	M4	M7
Standard Windows, programmer-oriented, text-editing features Fast and responsive interactive operation Tabbed multi-document interface for editing multiple source files (modules) Split-screen editing Regular expression support in Find / Replace Bookmarks Line modification indicators Optional line numbers, printing features etc. etc. The module in the current window is the target of the compiler / linker / builder User-customisable Tools menu for integrating batch files, Windows commands or 3rd-party applications Desktop HTML Help
Oberon Language-oriented Editing
Automatic syntax colouring of language elements as you type Auto-capitalisation of keywords as you type
Code Navigation
Alphabetical auto-indexed list of procedures. Click on the name to go to the procedure in the source code. Auto-indexed list of imported modules. Click on the module name to open the file.
General Language Features
Oberon is a general-purpose programming language first published in 1987. Conforms to the 2016 Standard Oberon Language Constant, Type, Variable and Procedure declarations Local and Global declarations Integer, Byte, Boolean, Char, Set and Procedure data types 32-bit IEEE Real data types and operations Array and Record structured data types Direct assignment of structured data types Pointers to Records for dynamic memory allocation Open array parameters If-elsif-else statements For, While and Repeat loops Case (switch) statements Nested procedures Type-extension capabilities for Object-Oriented programming Assertions for validating input / output parameters Type-checking / consistency validation across modules Read-only access to external global variables Nested comments
Embedded Programming Features / Language Extensions
Interrupt handling procedures Direct access to registers using SYSTEM.REG and SYSTEM.LDREG Type casting using SYSTEM.VAL Direct access to the Cortex-M REV, REV16 and REVSH instructions Explicit read / write access to memory-mapped peripheral device registers using SYSTEM functions GET and PUT Low-level SYSTEM functions ADR, BIT, EMIT etc. for absolute memory addressing, bit testing, emitting code instructions etc. Byte-level addressing of all built-in and user-defined data types and structures Inline bitfield insert and extract functions BFI and BFX
Performance Optimisation
Runtime checks are disabled locally in Leaf procedures
Registers are used instead of the stack to store selected local variables in Leaf procedures.
Single instructions used for DIV, MOD, RBIT, BFI and BFX
Cortex-M floating-point hardware used for real operations: add, subtract, multiply, divide and square root
Fast Native-code Compilation
Fast single-pass modular compilation One-click to compile the module in the current window Only the current module needs to be compiled if the interfaces of imported modules are unchanged Pre-compiled symbol files are used for fast access to imported modules Compilation continues to the end to find as many errors as possible Compilation errors are displayed in a separate window Click on an error line to take you to the actual line in the source
Linking / Building
Creates compact and fast native-code executables Automated Build feature identifies and recompiles all outdated modules before linking There is no need to maintain separate 'make' files. The names and locations of imported modules are already known at link time. Interfaces of imported modules are validated at link time to ensure consistency and eliminate obscure runtime errors Compile, link and build options are stored in configuration files Multiple projects for the same target can share a single configuration file Configuration file settings for multiple library search paths Configuration file settings for application code, data, stack and heap addresses User-customisable Tools menu to launch Windows applications or command-line utilities of your choice from the Astrobe menu
Debugging and Error trapping
Language support for validation of procedure parameters, pre- and post-conditions using assertions Compilation warnings for unused constants, types, variables, procedures and imported modules. Automatic array index bounds checking Runtime library Out can be used to send trace output to the Astrobe terminal window via a UART serial connection Runtime errors and failed assertions are identified by a callback trace with module and procedure names and source line numbers Source code of the Traps runtime library module can be user-customised
Uploading and Running
No special hardware flash programming tool is required Upload via USB drive Integrated terminal emulator communicates via a UART with a program running on the target device
General Library Modules
Out - Formatted ASCII text output of chars, strings and integers Strings - General text string processing Reals - Conversion of real numbers to and from strings Storage - Memory allocation / deallocation of pointer variables Math - Mathematical and trigonometrical functions LinkOptions - Access the user-supplied link-time configuration settings Graphics - Device-independent drawing of lines, circles and ellipses Random - Random number generation ResData - Resource data handling (constant data, images, fonts etc.) Traps - Runtime and assertion error handling Error - Standard error code definitions and messages Bits - Perform bitwise operations on INTEGERs Convert - Integer / string conversion Put - String handling helper functions DateTime - Date and time string conversion
Additional Library Modules
Main - Initialisation code required by the applications MCU - Definitions of peripheral register addresses to access the target's features e.g. GPIO, NVIC, RCC, RTC, I2C, SPI, Timers and USART. Serial - Serial input and output communication via USARTs Timers - Millisecond time measurement and delays Clock - Access the time components of the Real Time Clock SPI - Serial Peripheral Interface: control LCD displays, SD cards, 7-segment LEDs, and digital sensors such as accelerometers, magnetometers, etc. I2C - Control serial RAMs and EEPROMS, LCDs, accelerometers, temperature and pressure gauges, compasses etc. GPIO - General Purpose I/O Configuration and Control RTC - Set and retrieve the date and time components of the Real Time Clock HCDrive, HCDir, HCFiles - The HCFiler SDHC filesystem
Maximum RAM Size (KB)
STM32	32	128	192	512
Maximum Flash Size (KB)
STM32	256	1024	2048	2048
NOTE: The above RAM and Flash limits are imposed by the microcontrollers that are currently supported, not by Astrobe.
Source Code
Example modules
Full source code of library and runtime modules	Personal and Professional Editions
Disassemblers
Display the ARM assembler instructions generated for a module Display the ARM assembler instructions generated for the whole linked application	Personal and Professional Editions
Command-line Compiler, Linker and Builder
Compile, Link and Build applications using batch files, 3rd-party IDEs and build tools	Professional Edition
Commercial Applications
Develop and deploy commercial applications with no additional runtime fees	Professional Edition