Texas Instruments MSP430 Student Guide

MSP430 Memory
The flash memory is In-System Programmable (ISP), which means we can reprogram the
memory without taking the chip off of our boards or using difficult bed-of-nails methods. In fact,
you can program the flash using:
• An IDE, such as CCS or IAR. These debugging tools utilize the 4-wire JTAG or 2-wire SPI-
biwire emulation connections.
• The MSP430 Boot-Strap Loader supports a variety of connections and options. For example,
you can use the serial (or USB) interfaces to reprogram your devices. These interfaces are
popular on many manufacturing work flows.
• Finally, you can reprogram all – or part – of the flash memory via your own program running
on the device itself. Check out the MSP430ware FLASH driverlib functions.
On the ‘F5529, as with most MSP430 devices, the Flash actually consists of 3 regions.
Main
consists of the bulk of flash memory. This is where our programs are written to when using
the default project settings. Main flash consists of one contiguous memory; although, the Interrupt
Vectors are located inside of it at 0xFF80. If your device has more than 64K of flash, then some
will exist above and below the vectors – as shown in the diagram for the ‘F5529 (which has 128K
of flash).
Info Memory can be thought of as user data flash. Again, there are not any limitations on what
you store here, but these four segments are commonly used to hold calibration data or other non-
program items you want to store in non-volatile memory.
Boot Loader (BSL) holds the aforementioned boot loader code. This code, in turn, is used to
load new programs into Main flash. Please be aware that the BSL is handled differently amongst
the various generations of MSP430. In some cases, as with the ‘F5529, it is stored in its own
region of flash memory. On other devices, it may be hard-coded into the device.
RAM
RAM (Static Random Access Memory – SRAM) is found on every MSP430 device. Like flash,
though, the amount of RAM varies from device to device; and the amount of RAM memory is
often directly proportional to the cost of the device.
RAM is where most of the data is stored: everything from global variables, to stacks and heaps. It
is often thought of as the ‘working’ memory on the device. Even so, due to the ‘unified’ nature of
the MSP430 architecture, you can also move program code into RAM and run from this space.
The ‘F5529 has one aspect that is common among MSP430 devices which include the USB
peripheral. These devices have an extra 2KB of RAM; this RAM is dedicated to the USB
peripheral when it is in use, but available to your programs when the USB port is not being used.
Please refer to the USB Developers Package documentation to learn more about how the USB
protocol stack uses this RAM.
TLV
Although not ‘memory’, the Device Descriptors (TVL) does appear within the memory map. This
segment contains a tag-length-value (TLV) data structure that comprises a hierarchical
description (or on older devices, flat file description) of information such as: the device ID, die
revisions, firmware revisions, and other manufacturer and tool related information. Additionally,
these descriptors may contain information about the available peripherals, their subtypes and
addresses. This info may prove useful if building adaptive hardware drivers for operating
systems. (Note that some of the Value Line devices may not contain all of this information; and,
their factory supplied calibration data may reside in Info Memory A.)
1 - 18 MSP430 Workshop - Introduction to MSP430

Texas Instruments MSP430 Specifications

General

Brand	Texas Instruments
Model	MSP430
Category	Microcontrollers
Language	English