MAXQ2010 Maxim, MAXQ2010 Datasheet - Page 23

• Manufacturer Part Number: MAXQ2010
• Description: The MAXQ2010 microcontroller is a low-power, 16-bit device that incorporates a high-performance, 12-bit, multichannel ADC and a liquid-crystal display (LCD) interface
• Manufacturer: Maxim

applications, access to in-system programming, in-
application programming, or in-circuit debugging func-
tions is prohibited until a password has been supplied.
The password is defined as the 16 words of physical
program memory at addresses 0010h to 001Fh.
A single password lock (PWL) bit is implemented in the
SC register. When the PWL is set to 1 (power-on reset
default) and the contents of the memory at addresses
0010h to 001Fh are any value other than all FFh or 00h,
the password is required to access the utility ROM,
including in-circuit debug and in-system programming
routines that allow reading or writing of internal memory.
When PWL is cleared to 0, these utilities are fully acces-
sible without the password. The password is automati-
cally set to all 1s following a mass erase.
The microcontroller’s flash memory can be pro-
grammed by two different methods: in-system program-
ming and in-application programming. Both methods
afford great flexibility in system design and reduce the
life-cycle cost of the embedded system. These features
can be password protected to prevent unauthorized
access to code memory.
An internal bootstrap loader allows the device to be
reloaded over a simple JTAG interface. As a result,
software can be upgraded in-system, eliminating the
need for a costly hardware retrofit when updates are
required. Remote software updates enable application
updates to physically inaccessible equipment. The
interface hardware can be a JTAG connection to anoth-
er microcontroller, or a connection to a PC serial port
using a serial-to-JTAG converter such as the MAXQJ-
TAG-001, available from Maxim. If in-system program-
mability is not required, use a commercial gang
programmer for mass programming.
Activating the JTAG interface and loading the test
access port (TAP) with the system programming
instruction invokes the bootstrap loader. Setting the SPE
bit to 1 during reset through the JTAG interface exe-
cutes the bootstrap-loader-mode program that resides
in the utility ROM. When programming is complete, the
bootstrap loader can clear the SPE bit and reset the
device, allowing the device to bypass the utility ROM
and begin execution of the application software.
The following bootstrap loader functions are supported:
• Load
• Dump
• CRC
(Bootloader) In-System Programming
______________________________________________________________________________________
• Verify
• Erase
16-Bit Mixed-Signal Microcontroller
Programming
The in-application programming feature allows the
microcontroller to modify its own flash program memory
while simultaneously executing its application software.
This allows on-the-fly software updates in mission-criti-
cal applications that cannot afford downtime.
Alternatively, it allows the application to develop cus-
tom loader software that can operate under the control
of the application software. The utility ROM contains
user-accessible flash programming functions that erase
and program flash memory. These functions are
described in detail in the MAXQ Family User’s Guide:
MAXQ2010 Supplement .
Most functions of the device are controlled by sets of
registers. These registers provide a working space for
memory operations as well as configuring and address-
ing peripheral registers on the device. Registers are
divided into two major types: system registers and
peripheral registers. The common register set, also
known as the system registers, includes the ALU, accu-
mulator registers, data pointers, interrupt vectors and
control, and stack pointer. The peripheral registers
define additional functionality that may be included by
different products based on the MAXQ architecture.
This functionality is broken up into discrete modules so
that only the features required for a given product need
to be included.
The documentation on the module and register func-
tions is covered fully in the MAXQ Family User’s Guide
and the MAXQ Family User’s Guide: MAXQ2010
Supplement . This information includes the locations of
status and control bits and a detailed description of
their function and reset values. Refer to these docu-
ments for a complete understanding of the features and
operation of the microcontroller.
For maximum versatility, the device can generate its
internal system clock from several sources:
• External clock source
• Internal oscillator using external crystal or resonator
• FLL using 32kHz clock source (approximately 8MHz)
• FLL with no external crystal (approximately 5MHz)
Operation from an external clock source or internal
oscillator using external crystal or resonator is similar to
other microcontrollers. The designer must remember
that the rated maximum speed of operation applies to
the speed of the microcontroller core, not the external
with LCD Interface
In-Application Programming
System Timing
Register Set
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