The OPL notes I wrote in the late 90s and early 00s for the Nokia Communicators 9200, 9300 and 9500 series and Psion 5, 6 and 7 series. OPL is obviously a dead language now, but the routines can be quite useful as reference.
Read more about OPL here: https://en.wikipedia.org/wiki/Open_Programming_Language
OPL's main strength was the ease with which it could #include C++ libraries for PDA and mobile phone features such as camera, Bluetooth, IrDA, SMS, clipboard, touch-screen and much more.
dpNotes are a collection of - hopefully - useful ideas for the furtherance of OPL programming. In dpNotes we focus primarily on Symbian OS v6 (ER6) and later, though some of it was around already at v5 (ER5). A big difference between v1-v5 and v6-v7 and later is that the former was based on ASCII whereas the latter was on Unicode.
Clarification of OPL versions:
ER5 - Symbian v5, extended Ascii, Psion Series 5, Series 5mx, Series 7, netPad and netBook
ER5u - Symbian v5.1, Unicode, Ericsson R380
ER6 - Symbian v6, Nokia 92xx Communicators, Unicode
ER7 - Symbian v7, Nokia 9300, 9500 Communicators, Series 80, Series 90, UIQ and Series 60, Unicode
dpNote 0001 - Finding out the number of images in an MBM file
dpNote 0002 - Using the Nokia 9200 Series Communicator system fonts
dpNote 0003 - Getting the path to the location of an OPL application
dpNote 0004 - IOSEEK - documented and undocumented features
dpNote 0005 - Calculating UID checksum
dpNote 0006 - Handling of simple stacks
dpNote 0007 - Multi-dimensional arrays
dpNote 0008 - Stack of buffers with configurable size
dpNote 0009 - Getting the serial (IMEI) number of a Nokia 9200 Series Communicator
dpNote 0010 - Making the v6/S80 WINS Emulator more programmer friendly for OPL development
dpNote 0011 - Showing the amount of free memory
dpNote 0012 - Naming conventions
dpNote 0013 - Conversion between large hexadecimal and decimal numbers
dpNote 0014 - Useful POKEs and PEEKs
dpNote 0015 - Endianism
dpNote 0016 - Toolbar buttons with text only
dpNote 0017 - dpToolbar - a better Toolbar for Psion Teklogix netBook and Psion Series 7
dpNote 0018 - Loading a complete file into a buffer
dpNote 0019 - Converting long text buffers between Unicode and Ascii
dpNote 0020 - LOC function which gives correct answer for control and Unicode characters
dpNote 0021 - Character conversions
dpNote 0022 - Converting between Unicode and SCSU
dpNote 0023 - Clipboard - accurate copying and pasting of text in ER6 and ER7
dpNote 0024 - Adding a bitmap to an MBM file
dpNote 0025 - Useful IO functions and wrappers
dpNote 0026 - Predictable Pause
dpNote 0027 - Launching an application from OPL and wait until it finishes before returning
dpNote 0028 - Asynchronous event loop with inactivity timer
dpNote 0029 - Key event codes for Series 60 phones
dpNote 0030 - Returning more than one value
Documented in the OPLnotes PDF now.