M16C / 62N Group (80-pin)
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
Operation of Functional Blocks
The M16C/62N (80-pin version) group accommodates certain units in a single chip. These units include
ROM and RAM to store instructions and data and the central processing unit (CPU) to execute arithmetic/
logic operations. Also included are peripheral units such as timers, serial I/O, D-A converter, DMAC, CRC
calculation circuit, A-D converter, and I/O ports.
The following explains each unit.
Figure 1.4.1 is a memory map of the M16C/62N (80-pin version) group. The address space extends the 1M
bytes from address 0000016 to FFFFF16. From FFFFF16 down is ROM. For example, in the M30621MCN-
XXXGP, there is 128K bytes of internal ROM from E000016 to FFFFF16. The vector table for fixed interrupts
such as the reset and NMI are mapped to FFFDC16 to FFFFF16. The starting address of the interrupt
routine is stored here. The address of the vector table for timer interrupts, etc., can be set as desired using
the internal register (INTB). See the section on interrupts for details.
From 0040016 up is RAM. For example, in the M30621MCN-XXXGP, 10K bytes of internal RAM is mapped
to the space from 0040016 to 02BFF16. In addition to storing data, the RAM also stores the stack used when
calling subroutines and when interrupts are generated.
The SFR area is mapped to 0000016 to 003FF16. This area accommodates the control registers for periph-
eral devices such as I/O ports, A-D converter, serial I/O, and timers, etc. Figures 1.7.1 to 1.7.3 are location
of peripheral unit control registers. Any part of the SFR area that is not occupied is reserved and cannot be
used for other purposes.
The special page vector table is mapped to FFE0016 to FFFDB16. If the starting addresses of subroutines
or the destination addresses of jumps are stored here, subroutine call instructions and jump instructions
can be used as 2-byte instructions, reducing the number of program steps.
For details, see Figures
1.7.1 to 1.7.3
Internal RAM area
ROM size Address YYYYY16
Internal ROM area
Note : These memory maps show an instance in which PM13 is set to 0; but in the
case of products in which the internal RAM and the internal ROM are expanded
to over 15 Kbytes and 192 Kbytes, respectively, they show an instance in which
PM13 is set to 1.
Figure 1.4.1. Memory map