PIC16F946-ESLASHMLQTP datasheet(240/330 Pages) MICROCHIP

240 / 330 page

PIC16F913/914/916/917/946

DS41250F-page 238

16.6

Code Protection

If the code protection bit(s) have not been

programmed, the on-chip program memory can be

read out using ICSP for verification purposes.

16.7

ID Locations

Four memory locations (2000h-2003h) are designated

as ID locations where the user can store checksum or

other code identification numbers. These locations are

not accessible during normal execution, but are

readable and writable during Program/Verify mode.

Only the Least Significant 7 bits of the ID locations are

used.

16.8

In-Circuit Serial Programming

The PIC16F91X/946 microcontrollers can be serially

programmed while in the end application circuit. This is

simply done with two lines for clock and data and three

other lines for:

• power

• ground

• programming voltage

This allows customers to manufacture boards with

unprogrammed devices and then program the

microcontroller just before shipping the product. This

also allows the most recent firmware or a custom

firmware to be programmed.

The device is placed into a Program/Verify mode by

holding

the

RB7/ICSPDAT/ICDDAT/SEG13

and

RB6/ICSPCLK/ICDCK/SEG14 pins low, while raising

the MCLR (VPP) pin from VIL to VIHH. See

“PIC16F91X/946 Memory Programming Specification”

(DS41244) for more information. RB7 becomes the

programming data and the RB6 becomes the

programming clock. Both RB7 and RB6 are Schmitt

Trigger inputs in this mode.

After Reset, to place the device into Program/Verify

mode, the Program Counter (PC) is at location 0000h. A

6-bit command is then supplied to the device. Depending

on the command, 14 bits of program data are then

supplied to or from the device, depending on whether the

command was a load or a read. For complete details of

serial programming, please refer to the “PIC16F91X/946

Memory Programming Specification” (DS41244).

A typical In-Circuit Serial Programming connection is

shown in Figure 16-11.

FIGURE 16-11:

TYPICAL IN-CIRCUIT

SERIAL PROGRAMMING

CONNECTION

Note:

The entire data EEPROM and Flash

program memory will be erased when the

code protection is turned off. See the

“PIC16F91X/946 Memory Programming

Specification”

(DS41244)

for

information.

External

Connector

Signals

To Normal

Connections

To Normal

Connections

PIC® MCU

VDD

VSS

RE3/MCLR/VPP

RB6/ICSPCLK/

RB7/ICSPDATA/

+5V

VPP

CLK

Data I/O

* Isolation devices (as required)

ICDCK/SEG14

ICDDAT/SEG13

PIC16F946-E/MLQTP Datasheet(PDF) 240 Page - Microchip Technology

PIC16F946-E/MLQTP Datasheet(HTML) 240 Page - Microchip Technology

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL