PIC18LF252-I/SP Microchip Technology, PIC18LF252-I/SP Datasheet - Page 23

• Manufacturer Part Number: PIC18LF252-I/SP
• Description: IC MCU FLASH 16KX16 A/D 28DIP
• Manufacturer: Microchip Technology
• Series: PIC® 18Fr

Specifications of PIC18LF252-I/SP

• Program Memory Type: FLASH
• Program Memory Size: 32KB (16K x 16)
• Package / Case: 28-DIP (0.300", 7.62mm)
• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 40MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, LVD, POR, PWM, WDT
• Number Of I /o: 23
• Eeprom Size: 256 x 8
• Ram Size: 1.5K x 8
• Voltage - Supply (vcc/vdd): 2 V ~ 5.5 V
• Data Converters: A/D 5x10b
• Oscillator Type: External
• Operating Temperature: -40°C ~ 85°C
• Processor Series: PIC18LF
• Core: PIC
• Data Bus Width: 8 bit
• Data Ram Size: 1.5 KB
• Interface Type: MSSP, SPI, I2C, PSP, USART
• Maximum Clock Frequency: 40 MHz
• Number Of Programmable I/os: 23
• Number Of Timers: 1 x 16 bit
• Maximum Operating Temperature: + 85 C
• Mounting Style: Through Hole
• 3rd Party Development Tools: 52715-96, 52716-328, 52717-734, 52712-325, EWPIC18
• Development Tools By Supplier: PG164130, DV164035, DV244005, DV164005, PG164120, ICE2000, ICE4000, DM163022, DV164136
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 5 bit
• Package: 28SPDIP
• Device Core: PIC
• Family Name: PIC18
• Maximum Speed: 40 MHz
• Operating Supply Voltage: 2.5|3.3|5 V
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

FIGURE 4-4:
4.5
A data EEPROM address may be read via a sequence
of core instructions (4-bit command, ‘0000’) and then
output on SDATA via the 4-bit command, ‘0010’ (shift
out data holding register). The result may then be
immediately compared to the appropriate data in the
programmer’s memory for verification. Refer to
Section 4.4 for implementation details of reading data
EEPROM.
4.6
The term “Blank Check” means to verify that the device
has no programmed memory cells. All memories must
be verified: code memory, data EEPROM, ID locations,
and configuration bits. The Device ID registers
(3FFFFEh:3FFFFFh) should be ignored.
A “blank” or “erased” memory cell will read as a ‘1’. So,
“Blank Checking” a device merely means to verify that
all bytes read as FFh, except the configuration bits.
Unused (reserved) configuration bits will read ‘0’ (pro-
grammed). Refer to Table 5-2 for blank configuration
expect data for the various PIC18FXX2/XX8 devices.
 2010 Microchip Technology Inc.
SCLK
SDATA
Verify Data EEPROM
Blank Check
1
0
2
1
3
0
SHIFT OUT DATA HOLDING REGISTER TIMING (0010)
4
0
P5
SDATA = Input
1
2
3
4
5
6
7
8
P6
If it is determined that the device is not blank, then the
device should be Bulk Erased (see Section 3.1) before
any attempt to program is made.
Given that “Blank Checking” is merely code and data
EEPROM verification with FFh expect data, refer to
Section 4.4 and Section 4.2 for implementation details.
FIGURE 4-5:
9
LSb
P14
10
1
11
2
Blank Check Device
SDATA = Output
12
Shift Data Out
PIC18FXX2/XX8
3
13
blank?
device
Abort
4
Start
Is
14
5
No
BLANK CHECK FLOW
15
6
16
MSb
Yes
P5A
Fetch Next 4-bit Command
1
n
SDATA = Input
DS39576C-page 23
2
Continue
n
3
n
4
n