PIC12F508-I/SN Microchip Technology, PIC12F508-I/SN Datasheet - Page 15

• Manufacturer Part Number: PIC12F508-I/SN
• Description: IC MCU FLASH 512X12 8SOIC
• Manufacturer: Microchip Technology
• Series: PIC® 12Fr

Specifications of PIC12F508-I/SN

• Program Memory Type: FLASH
• Program Memory Size: 768B (512 x 12)
• Package / Case: 8-SOIC (3.9mm Width)
• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 4MHz
• Peripherals: POR, WDT
• Number Of I /o: 5
• Ram Size: 25 x 8
• Voltage - Supply (vcc/vdd): 2 V ~ 5.5 V
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Processor Series: PIC12F
• Core: PIC
• Data Bus Width: 8 bit
• Data Ram Size: 25 B
• Interface Type: RS- 232/USB
• Maximum Clock Frequency: 4 MHz
• Number Of Programmable I/os: 6
• Number Of Timers: 1
• Operating Supply Voltage: 2 V to 5.5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: 52715-96, 52716-328, 52717-734
• Development Tools By Supplier: PG164130, DV164035, DV244005, DV164005, PG164120, ICE2000, DV164101, DM163014, DV164120, DM163029
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: AC162059 - HEADER INTRFC MPLAB ICD2 8/14PIN
• Eeprom Size: -
• Data Converters: -
• Connectivity: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

5.0
For the PIC12F508/509, once code protection is
enabled, all program memory locations, 0x040-0x1FE
(F508) and 0x040-0x3FE (F509) inclusive, read all ‘0’s.
Program memory locations 0x000-0x03F, 0x1FF
(F508) and 0x3FF (F509) are always unprotected. The
user ID locations, backup OSCCAL location and the
Configuration Word read out in an unprotected fashion.
It is possible to program the user ID locations, backup
OSCCAL location and the Configuration Word after
code-protect is enabled.
5.1
It is recommended that the following procedure be
performed before any other programming is attempted.
It is also possible to turn code protection off (CP = 1)
using this procedure. However, all data within the
program memory will be erased when this
procedure is executed, and thus, the security of the
code is not compromised.
To disable code-protect:
a)
b)
c)
5.2
© 2007 Microchip Technology Inc.
Note:
Enter Program mode
Execute
command (001001)
Wait T
CODE PROTECTION
Disabling Code Protection
Embedding Configuration Word
and User ID Information in the
Hex File
ERA
Microchip Technology Incorporated feels
strongly that this feature is important for
the benefit of the end customer.
To allow portability of code, the program-
mer is required to read the Configuration
Word and user ID locations from the hex
file when loading the hex file. If Configura-
tion Word information was not present in
the hex file, then a simple warning
message may be issued. Similarly, while
saving a hex file, Configuration Word and
user ID information must be included. An
option to not include this information may
be provided.
Bulk
Erase
Program
Memory
Preliminary
5.3
5.3.1
Checksum is calculated by reading the contents of the
PIC12F508/509 memory locations and adding up the
opcodes up to the maximum user addressable location
(e.g., 0x1FF for the PIC12F508). Any Carry bits
exceeding 16 bits are neglected. Finally, the Configura-
tion Word (appropriately masked) is added to the
checksum. Checksum computation for the PIC12F508/
509 is shown in Table 5-1.
The checksum is calculated by summing the following:
• The contents of all program memory locations
• The Configuration Word, appropriately masked
• Masked user ID locations (when applicable)
The Least Significant 16 bits of this sum is the
checksum.
The following table describes how to calculate the
checksum for each device.
Note:
Checksum Computation
CHECKSUM
The checksum calculation differs depend-
ing on the code-protect setting. The
Configuration Word and user ID locations
can always be read regardless of the
code-protect settings.
PIC12F508/509
DS41227E-page 15