PIC16F505T-I/ST Microchip Technology, PIC16F505T-I/ST Datasheet - Page 16

• Manufacturer Part Number: PIC16F505T-I/ST
• Description: IC MCU FLASH 1KX12 14TSSOP
• Manufacturer: Microchip Technology
• Series: PIC® 16Fr

Specifications of PIC16F505T-I/ST

• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 20MHz
• Peripherals: POR, WDT
• Number Of I /o: 11
• Program Memory Size: 1.5KB (1K x 12)
• Program Memory Type: FLASH
• Ram Size: 72 x 8
• Voltage - Supply (vcc/vdd): 2 V ~ 5.5 V
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 14-TSSOP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Data Converters: -
• Connectivity: -

PIC16F505
5.0
For the PIC16F505, once code protection is enabled,
program memory locations 0x040-0x3FE inclusive,
read all ‘0’s. Program memory locations 0x000-0x03F
and 0x3FF are always unprotected. The user ID
locations, backup OSCCAL location and the Configura-
tion 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
DS41226G-page 16
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
To
programmer is required to read the
Configuration Word and user ID locations
from the hex file when loading the hex file.
If Configuration Word information was not
present in the hex file, then a simple
warning
Similarly,
Configuration
information must be included. An option to
not include this information may be
provided.
Microchip Technology Incorporated feels
strongly that this feature is important for
the benefit of the end customer.
.
Bulk
allow
message
Erase
while
portability
Word
saving
Program
may
and
of
a
be
code,
user
hex
Memory
issued.
file,
the
Preliminary
ID
5.3
5.3.1
Checksum is calculated by reading the contents of the
PIC16F505 memory locations and adding up the
opcodes up to the maximum user addressable location
(e.g., 0x3FF for the PIC16F505). Any carry bits
exceeding 16 bits are neglected. Finally, the Configura-
tion Word (appropriately masked) is added to the
checksum. Checksum computation for the PIC16F505
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 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
depending on the code-protect setting.
The Configuration Word and ID locations
can always be read regardless of the
code-protect settings.
checksum
 2010 Microchip Technology Inc.
calculation
differs