Searching \ for '[PIC]: PICLOADER Problem with 16F877' in subject line. ()
Make payments with PayPal - it's fast, free and secure! Help us get a faster server
FAQ page: www.piclist.com/techref/microchip/devices.htm?key=16F
Search entire site for: 'PICLOADER Problem with 16F877'.

Exact match. Not showing close matches.
PICList Thread
'[PIC]: PICLOADER Problem with 16F877'
2000\11\03@231703 by Ed Roberts

flavicon
face
I am trying to get PICLOADER going on a 20 MHz 16F877, and I am having problems downloading a program after installing PICLOADER.

I modified PICLOADER.ASM at line 78/9 to turn FULMEM on, the config line at 93 to have _HS_OSC rather than _XT_OSC, and at 268 to load D'125' rather than 25 for operation at 20 MHz. These mods seem to work, ie the PICLOADER program loads and comes up with its splash screen.
I can read to and write from the EEPROM, but I cant complete uploading a program.

When I try to upload, it clears the PIC in about 30 seconds, prompts ready, and then I paste the .hex file from Wordpad (2kbytes). At this point, there is traffic on the serial line for about 15 seconds, and then nothing. The bootloader doesnt come back with a status, and there is no response to the keyboard, including hitting carriage return. When I disconnect the connection via Hyperterm and reconnect, Q responds with no user code installed, as does D.

I have ensured that there is a carriage return at the end of the hex file (the file is generated by the P16PRO software, from Pascal code generated by P2C-Plus (Baranov)), and also tried inserting extra line feeds at the end of each hex line. I have set up Hyperterminal as per the release note, with the exception that I dont see a way to ensure the backspace key sends 'control H'. The version of Hyperterminal is 595160, copyright 1995.

Because I am using Pascal rather than C, I am not sure that I am correctly modifying the assembler code to start from address 3 rather than 0. However, I would have thought that would affect operation of the overlying code, not the bootloader's ability to load the code. (What I have done in the assembler is change org 0 to org 3, and a subsequent org 4  to org 8. It seems to assemble to hex code without complaint).

Any suggestions on what I should do would be appreciated.

Ed Roberts

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
"[PIC]:","[SX]:","[AVR]:"

2000\11\03@233934 by Bob Ammerman

picon face
Because I am using Pascal rather than C, I am not sure that I am correctly
modifying the assembler code to start from address 3 rather than 0. However,
I would have thought that would affect operation of the overlying code, not
the bootloader's ability to load the code. (What I have done in the
assembler is change org 0 to org 3, and a subsequent org 4  to org 8. It
seems to assemble to hex code without complaint).

The change from org 4 to org 8 is certainly _not_ a good thing.

org 4 defines the start of the interrupt handler.

What you need to do, is something like this:

Old  code:

   org    0
   something #1
   something #2
   something #3
   goto    someplace

   org    4
   something #4

   .
   .
someplace:
   something #5

New code:

   org    3
   goto    someplace

   org    4
   something #4

someplace:
   something   #1
   something   #2
   something   #3
   something   #5

Bob Ammerman
RAm Systems
(contract development of high performance, high function, low-level
software)


Any suggestions on what I should do would be appreciated.

Ed Roberts

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
"[PIC]:","[SX]:","[AVR]:" = ONLY! "[EE]:","[OT]:" =her "[BUY]:","[AD]:" ­s

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
"[PIC]:","[SX]:","[AVR]:"

More... (looser matching)
- Last day of these posts
- In 2000 , 2001 only
- Today
- New search...