UPSD3254 STMICROELECTRONICS [STMicroelectronics], UPSD3254 Datasheet - Page 114

• Manufacturer Part Number: UPSD3254
• Description: Flash Programmable System Devices with 8032 Microcontroller Core
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

UPSD3254A, UPSD3254BV, UPSD3253B, UPSD3253BV
– If a Reset Flash instruction is received, data in
Resume Sector Erase. If a Suspend Sector
Erase instruction was previously executed, the
erase cycle may be resumed with this instruction.
The Resume Sector Erase instruction consists of
writing 030h to any address while an appropriate
Sector Select (FS0-FS7 or CSBOOT0-CSBOOT3)
is High. (See Table 85.)
Specific Features
Flash Memory Sector Protect. Each
and secondary Flash memory sector can be sepa-
rately protected against Program and Erase cy-
cles. Sector Protection provides additional data
security because it disables all Program or Erase
cycles. This mode can be activated through the
JTAG Port or a Device Programmer.
Table 87. Sector Protection/Security Bit Definition – Flash Protection Register
Note:
Note: 1. Sector Protection/Security Bit Definition – Secondary Flash Protection Register
Note:
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Bit 7
Sec7_Prot
Bit 7
Security_Bit
the Flash memory sector that was being erased
is invalid.
Bit Definitions:
Sec<i>_Prot 1 = Primary Flash memory or secondary Flash memory Sector <i> is write-protected.
Sec<i>_Prot 0 = Primary Flash memory or secondary Flash memory Sector <i> is not write-protected.
Bit Definitions:
Sec<i>_Prot 1 = Secondary Flash memory Sector <i> is write-protected.
Sec<i>_Prot 0 = Secondary Flash memory Sector <i> is not write-protected.
Security_Bit 0 = Security Bit in device has not been set; 1 = Security Bit in device has been set.
Bit 6
Sec6_Prot
Bit 6
not used
Bit 5
Sec5_Prot
Bit 5
not used
Bit 4
Sec4_Prot
Bit 4
not used
primary
Bit 3
Sec3_Prot
Bit 3
Sec3_Prot
Sector protection can be selected for each sector
using the PSDsoft Express Configuration pro-
gram. This automatically protects selected sectors
when the device is programmed through the JTAG
Port or a Device Programmer. Flash memory sec-
tors can be unprotected to allow updating of their
contents using the JTAG Port or a Device Pro-
grammer. The MCU can read (but cannot change)
the sector protection bits.
Any attempt to program or erase a protected Flash
memory sector is ignored by the device. The Verify
operation results in a READ of the protected data.
This allows a guarantee of the retention of the Pro-
tection status.
The sector protection status can be read by the
MCU through the Flash memory protection regis-
ters (in the CSIOP block). See Table 87 and Table
1.
Bit 2
Sec2_Prot
Bit 2
Sec2_Prot
Bit 1
Sec1_Prot
Bit 1
Sec1_Prot
Bit 0
Sec0_Prot
Bit 0
Sec0_Prot