SyncMOS Technologies International, Inc.
SM59128
8-Bits Micro-controller
Embedded 128KB flash & 1KB RAM & IIC & SPWM
3.1 ISP Service Program
The ISP service program is a user-develop firmware program, which resides in the ISP service program space that is
reserved by N*512 bytes (N=0 to 8). After user develops the ISP service program, user shall determine the size of the
ISP service program space by setting a fittest N value before programming the ISP program code into the SM59128.
The ISP service program is developed by either IC vendor or user his own, and it shall include the features which relate
to the flash memory programming function as well as communication protocol between SM59128 and host device. For
example, if user utilizes UART interface to receive/transmit data between SM59128 and host device, the ISP service
program shall include baud rate, checksum, parity check or any error-checking mechanism to avoid data transmission
error.
User shall note the ISP service program can be initiated under active or idle mode, cannot be initiated under power
down mode.
3.2 Lock Bit (N)
The Lock Bit, N represents two functions, the first is for service program size configuration and the second is to protect
and prevent the ISP service program space from erase.
The address range for the ISP service program is from $F000H to $FFFFH of bank0 and $1F000H to $1FFFFH of
bank1. It can be divided to blocks of N*512 bytes (N=0 to 8). When N=0 means no ISP space, all of 128K byte flash
memory can be only used as program memory. When N=1 means ISP service program occupies 512 bytes , the rest of
63.5K bytes in both bank0 and bank1 can be used as program memory. The allowed maxima ISP service program
space is 4K bytes (N=8). Under such configuration, the usable program memory space is 60K bytes in each bank.
After the lock bit N is determined, SM59128 will reserve the ISP service program space downward from the top of the
program address $FFFFH of bank0 and $1FFFFH of bank1. The starting address of the ISP service program locates at
$Fx00H and $1Fx00H while x is an even number depending on the lock bit N. Please see page 7 to refer ISP service
program space structure.
The setting of lock bit N is different from the setting of flash protect function.
The ISP chip erase function is able to
erase all of the 128KB flash memory space except the locked ISP service program space of bank0 ( Note: The
locked ISP service program space of bank1 will be erased if user executes ISP chip erase function).
If SM59128
is not protected, the content of flash data is readable. If SM59128 is protected, the whole flash program memory space
including ISP service program can not be read.
3.3 Program the ISP Service Program
After setting the lock bit N and ISP service program has been programmed, the ISP service program memory will be
protected (locked) automatically. The lock bit N internally is controlled by a specific program/erase timing which is
different from the program/erase timing of flash function. User can erase the locked ISP service program by writer only.
The ISP chip erase function is able to erase all of the 128KB flash memory space except the locked ISP service
program space of bank0 ( Note: The locked ISP service program space of bank1 will be erased if user executes
ISP chip erase function).
User can not update any ISP service program code while SM59128 residents on system
board.
3.4 Initiate ISP Service Program
To initiate the ISP service program means to load the program counter (PC) with starting address of ISP service
program and execute. There are three ways to approach:
(1) Blank reset: When Hardware resets and the first address is blank ($0000=#FFH) will automatically load the PC
with starting address of ISP service program and execute.
Specifications subject to change without notice contact your sales representatives for the most recent information.
ISSFD-M027Ver: B SM59128
12
06/2009
SYNCMOS [ SYNCMOS TECHNOLOGIES,INC ]
