some differences: BASIC-programmable calculators often featured an additional "calculator-like" keyboard and a special calculator mode in which the system behaved like a scientific calculator. Pocket computers often offered additional programming languages as option. The Casio PB-2000 for example offered ANSI-C, BASIC, Assembler and Lisp. Companies often had both device types in their product portfolio. Casio, for example, sold some BASIC-programmable calculators as part of their "fx-" calculator series and pocket computer the dedicated "pb-" series while Sharp marketed all BASIC-programmable devices as pocket computers. Related tools Some programmable calculators have one or more methods of connecting to a PC for the interchange of data, programs, and software. These methods include IrDA, other wireless, serial ports -including USB or RS-232 via.125 inch or other size audio plugs, etc. Some of the latest programmable calculators contain cellular modems as an additional channel of connectivity. The programmable calculators can in many cases, via these connections, be used with peripherals such as data loggers and interfaces for instruments like thermometers, pH meters, weather instruments of all kinds, light meters, audio probes and microphones, dynamometers, pressure gauges, voltmeters, ammeters, ohm meters, atmospheric electricity measurement apparatus, ion counters, Geiger counters and scintillometers, altimeters, scales, accelerometers, and many others. Some machines can be used with oscilloscopes and their peripherals as well. Others can be configured—for example, collecting bio-feedback data by connecting devices for a pulse, blood pressure, oxygen saturation, galvanic skin resistance, body temperature, and even EKG and EEG probes to a data logger which is then connected to the calculator and, then or later, a PC. The HP programmables and others have an IrDA interface which allows them to interface with the printers specially designed for the calculators, HP's main lines of laser printers, computers, other calculators, and other devices. Also commonly available from many companies are small printers made specifically for calculators which tend to use cash register tape paper, ports and cables for connecting the calculators to a computer and/or another calculator, cassette recorders for recording programs and data, overhead projector displays, and connectors for auxiliary display devices. The earlier programmable calculators, as well as the pocket computers mentioned above, also had such things as video interfaces for televisions and composite monitors, 2½ inch mini floppy disc drives, bar-code readers, and standard RS-232 connectivity which provided for other such things as modems, external hard drives and more. The printer selection for the pocket computers