st62t65b STMicroelectronics, st62t65b Datasheet - Page 14

• Manufacturer Part Number: st62t65b
• Description: 8-bit Otp/eprom Mcus With A/d Converter, Auto-reload Timer, Eeprom And Spi
• Manufacturer: STMicroelectronics

14
ST62T55B ST62T65B/E65B
1.4 PROGRAMMING MODES
1.4.1 Option Byte
The Option Byte allows configuration capability to
the MCUs. Option byte’s content is automatically
read, and the selected options enabled, when the
chip reset is activated.
It can only be accessed during the programming
mode. This access is made either automatically
(copy from a master device) or by selecting the
OPTION BYTE PROGRAMMING mode of the pro-
grammer.
The option byte is located in a non-user map. No
address has to be specified.
EPROM Code Option Byte
PROTECT. This bit allows the protection of the
software contents against piracy. When the bit
PROTECT is set high, readout of the OTP con-
tents is prevented by hardware. No programming
equipment is able to gain access to the user pro-
gram. When this bit is low, the user program can
be read.
EXTCNTL . This bit selects the External STOP
Mode capability. When EXTCNTL is high, pin NMI
controls if the STOP mode can be accessed when
the watchdog is active. In addition, PB0 is forced
as open drain output. When EXTCNTL is low, the
STOP instruction is processed as a WAIT as soon
as the watchdog is active.
PB2-3 PULL . When set this bit removes pull-up at
reset on PB2-PB3 pins. When cleared PB2-PB3
pins have an internal pull-up resistor at reset.
PB0-1 PULL . When set this bit removes pull-up at
reset on PB0-PB1 pins. When cleared PB0-PB1
pins have an internal pull-up resistor at reset.
WDACT . This bit controls the watchdog activation.
When it is high, hardware activation is selected.
The software activation is selected when WDACT
is low.
DELAY. This bit enables the selection of the delay
internally generated after pin RESET is released.
When DELAY is low, the delay is 2048 cycles of
14/74
PRO-
TECT
7
EXTC -
NTL
PB2-3
PULL
PB0-1
PULL
WDACT DELAY OSCIL
0
-
the oscillator, it is of 32768 cycles when DELAY is
high.
OSCIL. When this bit is low, the oscillator must be
controlled by a quartz crystal, a ceramic resonator
or an external frequency. When it is high, the oscil-
lator must be controlled by an RC network, with
only the resistor having to be externally provided.
D0. Reserved. Must be cleared to zero.
The Option byte is written during programming ei-
ther by using the PC menu (PC driven Mode) or
automatically (stand-alone mode)
1.4.2 Program Memory
EPROM/OTP programming mode is set by a
+12.5V voltage applied to the TEST/V
programming flow of the ST62T65B/E65B is de-
scribed in the User Manual of the EPROM Pro-
gramming Board.
The MCUs can
ST62E6xB EPROM programming tools available
from SGS-THOMSON.
Table 5. ST6255B, ST62T65B/E65B
Note: OTP/EPROM devices can be programmed
with
SGS-THOMSON
ST626X-KIT).
1.4.3 EEPROM Data Memory
EEPROM data pages are supplied in the virgin
state FFh. Partial or total programming of EEP-
ROM data memory can be performed either
through the application software, or through an ex-
ternal programmer. Any SGS-THOMSON tool
used for the program memory (OTP/EPROM) can
also be used to program the EEPROM data mem-
ory.
Device Address
0FFCh-0FFDh
0FA0h-0FEFh
0FFEh-0FFFh
0FF0h-0FF7h
0FF8h-0FFBh
the development
0000h-007Fh
0080h-0F9Fh
Program Memory Map
be programmed
(ST62E6X-EPB
tools available
NMI Interrupt Vector
Interrupt Vectors
Reset Vector
Description
User ROM
Reserved
Reserved
Reserved
PP
with the
pin. The
from
or