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billroy / bitlash

Bitlash: a programmable command shell for arduino
http://bitlash.net
MIT License
341 stars 73 forks source link

run bitlash code stored in flash #44

Closed pwl42 closed 9 years ago

pwl42 commented 9 years ago

hi Bill, have you ever built a version that would interpret bitlash code that is stored in the unused part of flash (on a 32K mcu)? it seems to me that would be a good place to put a larger program.

billroy commented 9 years ago

Hello and thanks for your question.

You can define functions in flash by adding them to the “builtin_table” data structure in the file src/bitlash-builtins.c; see the doc there for the use of the BUILT_IN macro. Functions built-in this way can be run just like eeprom functions.

I hope that helps, and I’m happy to take followup questions.

-br

On Mar 20, 2015, at 2:38 PM, pwl42 notifications@github.com wrote:

hi Bill, have you ever built a version that would interpret bitlash code that is stored in the unused part of flash (on a 32K mcu)? it seems to me that would be a good place to put a larger program.

— Reply to this email directly or view it on GitHub https://github.com/billroy/bitlash/issues/44.

pwl42 commented 9 years ago

I guess I am just being too picky. I would prefer to load unused flash memory blocks with bitlash code and have it executed the same way as code in eeprom. Those blocks could be replaced without recompiling. Of course, this would be useful only on the larger devices.

On the internet nobody can hear you being subtle. --Linus Torvalds

On Fri, 3/20/15, Bill Roy notifications@github.com wrote:

Subject: Re: [bitlash] run bitlash code stored in flash (#44) To: "billroy/bitlash" bitlash@noreply.github.com Cc: "pwl42" pwl42@yahoo.com Date: Friday, March 20, 2015, 8:23 PM

Hello and thanks for your question.

You can define functions in flash by adding them to the “builtin_table” data structure in the file src/bitlash-builtins.c; see the doc there for the use of the BUILT_IN macro. Functions built-in this way can be run just like eeprom functions.

I hope that helps, and I’m happy to take followup questions.

-br

On Mar 20, 2015, at 2:38 PM, pwl42 notifications@github.com wrote:

hi Bill,

have you ever built a version that would interpret bitlash code that is stored in the unused part of flash (on a 32K mcu)? it seems to me that would be a good place to put a larger program.

—

Reply to this email directly or view it on GitHub https://github.com/billroy/bitlash/issues/44.

— Reply to this email directly or view it on GitHub.

billroy commented 9 years ago

Thanks for clarifying. If I understand correctly, you would like to write the flash dynamically at runtime, like the eeprom.

Last time I checked, it was considered tricky to write to flash at runtime, and there were no libraries available to do it.

If, however, someone has developed a library to write to flash at runtime, this would not be a difficult feature to implement.

-br

On Mar 21, 2015, at 2:16 AM, pwl42 notifications@github.com wrote:

I guess I am just being too picky. I would prefer to load unused flash memory blocks with bitlash code and have it executed the same way as code in eeprom. Those blocks could be replaced without recompiling. Of course, this would be useful only on the larger devices.

On the internet nobody can hear you being subtle. --Linus Torvalds

On Fri, 3/20/15, Bill Roy notifications@github.com wrote:

Subject: Re: [bitlash] run bitlash code stored in flash (#44) To: "billroy/bitlash" bitlash@noreply.github.com Cc: "pwl42" pwl42@yahoo.com Date: Friday, March 20, 2015, 8:23 PM

Hello and thanks for your question.

You can define functions in flash by adding them to the “builtin_table” data structure in the file src/bitlash-builtins.c; see the doc there for the use of the BUILT_IN macro. Functions built-in this way can be run just like eeprom functions.

I hope that helps, and I’m happy to take followup questions.

-br

On Mar 20, 2015, at 2:38 PM, pwl42 notifications@github.com wrote:

hi Bill,

have you ever built a version that would interpret bitlash code that is stored in the unused part of flash (on a 32K mcu)? it seems to me that would be a good place to put a larger program.

—

Reply to this email directly or view it on GitHub https://github.com/billroy/bitlash/issues/44.

— Reply to this email directly or view it on GitHub.

— Reply to this email directly or view it on GitHub https://github.com/billroy/bitlash/issues/44#issuecomment-84278588.

pwl42 commented 9 years ago

I was thinking that I would write to those unused blocks when I loaded bitlash and If I needed to change them later I would use avrdude. Is the flash readable only as 16 bit words and, if so, is that a problem?

On the internet nobody can hear you being subtle. --Linus Torvalds

On Sat, 3/21/15, Bill Roy notifications@github.com wrote:

Subject: Re: [bitlash] run bitlash code stored in flash (#44) To: "billroy/bitlash" bitlash@noreply.github.com Cc: "pwl42" pwl42@yahoo.com Date: Saturday, March 21, 2015, 7:17 AM

Thanks for clarifying. If I understand correctly, you would like to write the flash dynamically at runtime, like the eeprom.

Last time I checked, it was considered tricky to write to flash at runtime, and there were no libraries available to do it.

If, however, someone has developed a library to write to flash at runtime, this would not be a difficult feature to implement.

-br

On Mar 21, 2015, at 2:16 AM, pwl42 notifications@github.com wrote:

I guess I am just being too picky. I would prefer to load unused flash memory blocks with bitlash code and have it executed the same way as code in eeprom. Those blocks could be replaced without recompiling. Of course, this would be useful only on the larger devices.

On the internet nobody can hear you being subtle. --Linus Torvalds

On Fri, 3/20/15, Bill Roy notifications@github.com wrote:

Subject: Re: [bitlash] run bitlash code stored in flash (#44)

To: "billroy/bitlash" bitlash@noreply.github.com

Cc: "pwl42" pwl42@yahoo.com

Date: Friday, March 20, 2015, 8:23 PM

Hello and thanks for your question.

You can define functions in flash by adding them to the

“builtin_table” data structure in the file

src/bitlash-builtins.c; see the doc there for the use of the

BUILT_IN macro. Functions built-in this way can be run just

like eeprom functions.

I hope that helps, and I’m happy to take followup

questions.

-br

On Mar 20, 2015, at 2:38 PM, pwl42

notifications@github.com wrote:

hi Bill,

have you ever built a version that would interpret

bitlash code that is stored in the unused part of flash (on

a 32K mcu)? it seems to me that would be a good place to put

a larger program.

—

Reply to this email directly or view it on GitHub

https://github.com/billroy/bitlash/issues/44.

—

Reply to this email directly or view

it on GitHub.

—

Reply to this email directly or view it on GitHub https://github.com/billroy/bitlash/issues/44#issuecomment-84278588.

— Reply to this email directly or view it on GitHub.

billroy commented 9 years ago

IIRC the flash is only writable in pages of some size considerably greater than one byte. And I believe there is some complication about having to be in bootloader mode to write to it, though I may be recalling that incorrectly.

-br

On Mar 21, 2015, at 7:22 AM, pwl42 notifications@github.com wrote:

I was thinking that I would write to those unused blocks when I loaded bitlash and If I needed to change them later I would use avrdude. Is the flash readable only as 16 bit words and, if so, is that a problem?

On the internet nobody can hear you being subtle. --Linus Torvalds

On Sat, 3/21/15, Bill Roy notifications@github.com wrote:

Subject: Re: [bitlash] run bitlash code stored in flash (#44) To: "billroy/bitlash" bitlash@noreply.github.com Cc: "pwl42" pwl42@yahoo.com Date: Saturday, March 21, 2015, 7:17 AM

Thanks for clarifying. If I understand correctly, you would like to write the flash dynamically at runtime, like the eeprom.

Last time I checked, it was considered tricky to write to flash at runtime, and there were no libraries available to do it.

If, however, someone has developed a library to write to flash at runtime, this would not be a difficult feature to implement.

-br

On Mar 21, 2015, at 2:16 AM, pwl42 notifications@github.com wrote:

I guess I am just being too picky. I would prefer to load unused flash memory blocks with bitlash code and have it executed the same way as code in eeprom. Those blocks could be replaced without recompiling. Of course, this would be useful only on the larger devices.

On the internet nobody can hear you being subtle. --Linus Torvalds

On Fri, 3/20/15, Bill Roy notifications@github.com wrote:

Subject: Re: [bitlash] run bitlash code stored in flash (#44)

To: "billroy/bitlash" bitlash@noreply.github.com

Cc: "pwl42" pwl42@yahoo.com

Date: Friday, March 20, 2015, 8:23 PM

Hello and thanks for your question.

You can define functions in flash by adding them to the

“builtin_table” data structure in the file

src/bitlash-builtins.c; see the doc there for the use of the

BUILT_IN macro. Functions built-in this way can be run just

like eeprom functions.

I hope that helps, and I’m happy to take followup

questions.

-br

On Mar 20, 2015, at 2:38 PM, pwl42

notifications@github.com wrote:

hi Bill,

have you ever built a version that would interpret

bitlash code that is stored in the unused part of flash (on

a 32K mcu)? it seems to me that would be a good place to put

a larger program.

—

Reply to this email directly or view it on GitHub

https://github.com/billroy/bitlash/issues/44.

—

Reply to this email directly or view

it on GitHub.

—

Reply to this email directly or view it on GitHub https://github.com/billroy/bitlash/issues/44#issuecomment-84278588.

— Reply to this email directly or view it on GitHub.

— Reply to this email directly or view it on GitHub https://github.com/billroy/bitlash/issues/44#issuecomment-84333574.