Micromite Plus Manual Page 3
Introduction
This section provides an introduction for users who are familiar with the Micromite and need a summary of the
extra features in the Micromite Plus.
The Micromite Plus is an extension of the standard Micromite; all features of the standard Micromite are also
supported in the Micromite Plus. This includes features of the BASIC language, input/output, communications,
etc. Some commands have changed slightly (for example the CPU command) but for the main part Micromite
programs will run unchanged on the Micromite Plus.
The following summarises the new features in the Micromite Plus as compared to the standard Micromite:
MX470 Processor
The Micromite Plus is based on the Microchip PIC32MX470 32 bit microcontroller. This chip is available in
64 and 100-pin surface mount packages and is two to three times faster than the MX170 chip used in the
standard Micromite. In BASIC the space available for both programs and variables is doubled to approx 100
KB flash and 100KB RAM.
The Micromite Plus uses a crystal for timekeeping. This allows the Micromite Plus to support USB
communications and also ensures that its internal clocks are much more accurate.
I/O Pins
The 64-pin Micromite Plus has up to 45 free I/O pins and the 100-pin chip 77. Of these 28 pins (on either chip)
can be analog inputs.
The Micromite Plus has two SPI ports and up to four serial COM ports. All serial COM ports are high speed
(over 1,000,000 baud). The provision of two SPI ports means that one can be used for SPI LCD's, touch and
SD card interfaces leaving the other entirely free for use in a BASIC program. If the SPI is not used for these
features then both SPI interfaces can be used in BASIC programs.
USB
The Micromite Plus has a built in USB 2.0 interface which will work at all CPU frequencies at 20MHz or more.
The USB is integrated in the chip and no other hardware or components are required. MMBasic uses the USB
CDC protocol which allows the USB interface to be used as the console with a host computer running a
terminal emulator such as Tera Term.
The USB console operates in parallel with the serial console, anything received from either of the inputs is
placed in the input queue for the interpreter or the program to read and anything outputted by the program or
interpreter will be sent to either devices.
The USB feature is optional, if nothing is connected to the USB interface MMBasic will ignore it.
SD Card
The Micromite Plus includes full support for SD cards. This includes opening files for reading, writing or
random access and loading and saving programs. The firmware will work with cards up to 64GB formatted in
FAT16 or FAT32 and the files created can also be read and written on personal computers running Windows,
Linux or the Mac operating system.
Up to 10 files can be open simultaneously. Using the OPEN command files can be opened and read from using
INPUT, LINE INPUT, or INPUT$() or written to using PRINT or WRITE with. A program can be saved using
the SAVE command and reloaded or run using LOAD. Programs and files stored on the card can be listed with
the FILES command and deleted using the KILL command. The current working directory can be changed
using CHDIR and a new directory be created with MKDIR.
The LOAD IMAGE command can be used to load a bitmap image from the SD card and display it on an
attached LCD display panel. This can be used to draw a logo or add a background on the display.
The SD card feature is entirely optional and MMBasic will operate normally if it is not used.
LCD Display Panels
Micromite Plus supports two additional LCD panels that use SPI controllers (the ST7735 and ILI9163) and also
parallel LCD displays that use the SSD1963 controller.
SSD1963 based LCD panels are available in sizes from 4.3 inch to 8 inch for prices that range from US$30 to
US$60 on eBay. They use a parallel interface so the Micromite Plus can transfer data much faster than via SPI
resulting in a very quick screen update. These displays are also much larger, have more pixels and are brighter.
MMBasic will drive them using 24-bit true colour for a full colour rendition (16 million colours).
