HEF memory is located in the last 128 bytes of Program memory, This is the same range of memory where the Tinybooltloader firmware resides. Therefore writing to HEF memory will clobber the bootloader firmware resulting in a chip that will not boot up.
To use a bootloader AND HEF, a bootloader that resides below the HEF memory range must be used.
William
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HEF memory is located in the last 128 bytes of Program memory, This is the same range of memory where the Tinybooltloader firmware resides. Therefore writing to HEF memory will clobber the bootloader firmware resulting in a chip that will not boot up.
To use a bootloader AND HEF, a bootloader that resides below the HEF memory range must be used.
William
Hi Willi,
This post was last year, but will address it for GCBasic users who want to
implement HEF with TinyBootloader.
See diagram below.
In the example you create HEF space below the BootLoader
with entries as such
addwf PCL,F
retlw ’B' ;ASCII
retlw 0x55 ;Hex
retlw 29 ;Decimal
You will have to account for 16words extra as part of BootLoader in
piccodes.ini.
Example:
; PIC10 family
; example: PIC10F322 Flash: 512 words = 200h; 200h2 = 400h
; $yy, B, |PIC |(Boot |200h2 |EE |Boot |Erase,
;-----------------------------------------------------------
$12, B, 10F322 (100W), $400, $000, 200, 32, ;Without (HEF)
$13, B, 10F322 (116W), $400, $000, 232, 32, ;With 16bytes (HEF) as EE data
Cheers,
Hanspeter.