PIC18F8520-I/PTG Microchip Technology, PIC18F8520-I/PTG Datasheet - Page 20

• Manufacturer Part Number: PIC18F8520-I/PTG
• Description: IC MCU FLASH 16KX16 80TQFP
• Manufacturer: Microchip Technology
• Series: PIC® 18Fr

Specifications of PIC18F8520-I/PTG

• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 40MHz
• Connectivity: EBI/EMI, I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, LVD, POR, PWM, WDT
• Number Of I /o: 68
• Program Memory Size: 32KB (16K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 1K x 8
• Ram Size: 2K x 8
• Voltage - Supply (vcc/vdd): 4.2 V ~ 5.5 V
• Data Converters: A/D 16x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 80-TFQFP
• For Use With: XLT80PT3 - SOCKET TRAN ICE 80MQFP/TQFPAC164320 - MODULE SKT MPLAB PM3 80TQFPAC174011 - MODULE SKT PROMATEII 80TQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

PIC18FXX20
4.0
4.1
Code memory is accessed one byte at a time via the
4-bit command, ‘1001’ (Table Read, post-increment).
The contents of memory pointed to by the Table Pointer
(TBLPTRU:TBLPTRH:TBLPTRL) are loaded into the
Table Latch and then serially output on SDATA.
TABLE 4-1:
FIGURE 4-1:
DS39583C-page 20
Step 1: Set Table Pointer.
Step 2: Read memory into Table Latch and then shift out on SDATA, LSb to MSb.
SCLK
SDATA
Command
0000
0000
0000
0000
0000
0000
1001
4-Bit
READING THE DEVICE
Read Code Memory, ID Locations,
and Configuration Bits
1
1
0E <Addr[21:16]>
6E F8
0E <Addr[15:8]>
6E F7
0E <Addr[7:0]>
6E F6
00 00
READ CODE MEMORY SEQUENCE
2
0
3
Data Payload
TABLE READ POST-INCREMENT INSTRUCTION TIMING (1001)
0
4
1
P5
SDATA = Input
1
2
3
MOVLW Addr[21:16]
MOVWF TBLPTRU
MOVLW <Addr[15:8]>
MOVWF TBLPTRH
MOVLW <Addr[7:0]>
MOVWF TBLPTRL
TBLRD *+
4
5
6
7
8
P6
The 4-bit command is shifted in LSb first. The Table
Read is executed during the next 8 clocks, then shifted
out on SDATA during the last 8 clocks, LSb to MSb. A
delay of P6 must be introduced after the falling edge of
the 8th SCLK of the operand to allow SDATA to
transition from an input to an output. During this time,
SCLK must be held low (see Figure 4-1). This operation
also increments the Table Pointer by one, pointing to the
next byte in code memory for the next read.
This technique will work to read any memory in the
000000h to 3FFFFFh address space, so it also applies
to the reading of the ID and Configuration registers.
9
LSb
P14
10
1
Core Instruction
11
2
SDATA = Output
12
Shift Data Out
3
13
4
14
5
15
 2010 Microchip Technology Inc.
6
16
MSb
P5A
Fetch Next 4-bit Command
1
SDATA = Input
n
2
n
3
n
4
n