inside a hex file

[overmind]

hi everybody.. all these terms have really got me tangled up. what i want to create is a downloader that downloads hex files of compiled ccs codes like (ex_swt.c) into the pic.. the pic on my development board has already has its firmware programmed before. so that is not what i want. what i want to create is a downloader or whatever its called..

Your binary data are(in hex): 0x3000, 0x008A, 0x289A, 0x0000, 0x3023,.... with the checksum 0xFF at the end. These are placed into each address location of the PIC flash memory. Notices that because every word is 14-bit wide, the two MSDs would have to be in the range 0x00~0x3F.

To understand how one can handle these data and actually send them into the PIC, you need to get hold of the Microchip programming Spec document 39589b. It is for 16F87XA. I searched but there is no such document for 16F87X. Read it until you understand its content.

thank you eblc1388.. you shed a bright light on my problem.. now i can working on my downloader.. and thanks also for the people who took time to help me with my problem. thats the reason why i love this forum because of people like you..

 

[eblc1388]

you need to get hold of the Microchip programming Spec document 39589b. It is for 16F87XA. I searched but there is no such document for 16F87X. Read it until you understand its content.

I found out the answer.

The document was called "16F87X EEPROM Memory Programming Specification" DS39025E instead.

It includes the flash memory programming as well.

 

[Nigel Goodwin]

I found out the answer.

The document was called "16F87X EEPROM Memory Programming Specification" DS39025E instead.

It includes the flash memory programming as well.

No, it's called 'EEPROM Memory Programming' because it's an EEPROM chip, not a FLASH one - many that claim to be FLASH are actually EEPROM technology (ATMEL first started calling EEPROM, FLASH, and MicroChip eventually copied them).

 

[techmanx]

HI,
perhaps you like re-inventing, but if not there are quite a few free software compilers, etc. on the web. If you go to www.microcircuits.com, you can download the complete package PVDASM. this package copes with almost every need. Wish you luck and fun, Brian

 

[Nigel Goodwin]

Perhaps you might try reading the thread?, of what use is a link to a useless website (which doesn't even mention what you quoted), and an Intel 8086 disassembler?.

It's rather vague what he's trying to do?, but it's certainly PIC based, and appears to be to write his own PIC programmer software? - why he can't use one of the many already out there, I don't know?.

 

[Nigel Goodwin]

Here's a quick snippet from a MicroChip datasheet, briefly explaining the HEX file format.

Standard hex file format for serial programming:
The hex file containing the ‘serial numbers’ will be in
Intel hex 8-bit format. Since the PIC16C5X and the
PIC16C5XA have 12-bit data words, all addresses are
doubled in this hex format. Each line of the hex file will
be for a new part. Each line can contain only up to 16
bytes (i.e. eight PIC16C5X, PIC16C5XA instruction
words). The format is as follows:
:
NNAAAATTHHHHHH......HHCC
where:
NN = byte count on current line (max 10h allowed)
AAAA = address in four hex digits
TT = record type, always 00 except 01 for EOF
HH = Two digit hex data byte
CC = Two digit hex checksum

 

[overmind]

hi sir nigel, yes im just doing it out of curiosity sake.. i was just intrigued how hex codes go into the pic. that's all. thanks.

 

[Nigel Goodwin]

hi sir nigel, yes im just doing it out of curiosity sake.. i was just intrigued how hex codes go into the pic. that's all. thanks.

Check the original David Tait software, there are examples written using BASIC, which should help you somewhat?.

 

[3v0]

Based on his previous posts he has a custom 16F877 board with what appears to be a bootload on it.
Pretty sure he does not have a hardware programmer.

Based on what he has said I do not think you can take what he says at face value. He may not understand the differance between a bootloader and a programmer.

hi everybody.. all these terms have really got me tangled up. what i want to create is a downloader that downloads hex files of compiled ccs codes like (ex_swt.c) into the pic.. the pic on my development board has already has its firmware programmed before. so that is not what i want. what i want to create is a downloader or whatever its called..

It could be that there is a bootloader on the chip. Or it could be that he wants to reprogram a chip with unwanted firmware on it.

overmind:
A programmer is hardware+software that can program a PIC regardless of what is already on the PIC.

A bootloader allows you to download additional programs without the use of a programmer. But PICs do not come with bootloaders, you need a programmer to program the bootloader onto the PIC. Once programmed the bootloader can load additional code as needed. A bootloader does not need special hardware, it most often used with a PC's RS232 port.

If you do not have a PIC programmer, or a PIC already programmed with a bootloader, you can not use a bootloader.

If you want a programmer you can buy or build one. Download free software.

As I said earlier: CCS already has a bootloader to program into the PIC EX_BOOTLOADER.C /loader.c
and a program SIOW.EXE that runs on the PC to download the program.

Why do you want to make your own ?

 

[Mike - K8LH]

The Intel Hex File format is shown in section 1.7.5 in my MPASM Assembler User's Guide (33014J).

I also gained quite a bit of understanding by studying early examples of a Microchip 16F877 bootloader program. From those two sources I gleaned much valuable information for designing my own Assembler and C bootloader programs...

Good luck, Mike

;
;  NEWLN processes a hex record text line from the serial port.
;
;  HyperTerminal should be set to 19.2 kb, 8 data bits, 1 stop bit,
;  no parity, <Xon>/<Xoff> (software) handshaking, no 'echo', and
;  2-msec line delay.
;
;  each 'hex record' starts with a colon (":") character, ends with
;  <cr> and <lf> characters, and looks something like this;
;
;  <:><bytecount><addrh><addrl><type><data>..<data><chksum><cr><lf>
;
;  the <addrh> and <addrl> "byte" address must be converted into a
;  "word" address for EEADR and EEADRH before write operations.
;
;  <type> field values
;   00 = Data Record > address and data
;   01 = End of File Record
;   02 = Segment Address Record > ?
;   04 = Linear Address Record > two byte extended address
;        (18F' > 0000=Program, 0020=IDLocs, 0040=Config, 00F0=EEProm)
;
;  one Linear Address Record (type=04) appears at the beginning of
;  16F87/88 Hex files (":020000040000FA") with an address of 0000h.
;
;  the 16F87/88 only supports writing program/flash and data/eeprom
;  memory from within a program.  no IDLOCS or configuration bits.
;

 

[Mike - K8LH]

Just read 3V0's post and suspect I may have also misunderstood the OPs request. Sorry...