Hi,
I have recently inherited a project that was originally done using an 8051. A few years ago the hardware was changed to use an 80C251SB but development continued using the C51 compiler.
There is no external data memory in the device. Is it possible to use the 80C251SB's larger internal data memory with the C51 compiler? We have uVision3 with C51 compiler version 8.09.
My bosses want to add PID and serial communication to the device (serial hardware is there but has never been used) and it looks like I've only got about 20 bytes left to work with.
a project that was originally done using an 8051. A few years ago the hardware was changed to use an 80C251SB but development continued using the C51 compiler. In that case get rid of the 251 and replace it with one of the many '51s now available with tons of internal memopry and speeds that leave the 251 in the dust.
There is no external data memory in the device. Is it possible to use the 80C251SB's larger internal data memory with the C51 compiler? We have uVision3 with C51 compiler version 8.09. Have no idea, but if you do as above you will have oodles and bunches of memory.
My bosses want to add PID and serial communication to the device (serial hardware is there but has never been used) and it looks like I've only got about 20 bytes left to work with. with the suggestion at the top, you will have bytes galore, there is no way in hades you will get any addition to work in 20 bytes.
anyhow "add serial communication" means a hardware change, so replacing the discontinued 251 is a no brainer.
Erik
"serial hardware is there but has never been used" gives an indication that the original hardware already has everything needed for serial communication, but that the original project didn't had the time to implement any support for it (or they run out of memory and decided to skip the support).
gives an indication
oh glory day when we can post based on knowledge, not 'indications'
there is another 'indication' in the original post "20 bytes left" with no telling if it is code or data.
Data. I thought that was clear from the post topic. I want to know if I can use the larger internal data memory of the 251, using C51. I've got plenty of space still for code.
I thought that was clear from the post topic.
It was. Sadly though some contributors are not well known for their ability to read and understand a post especially if it mentions a piece of hardware they don't like/understand/use. The red mist descends as an apoplectic burst of unsubstantiated opinion spews forth.
Never having used a 251 I cannot answer your question with certainty but suspect that you cannot access more than the 256 bytes of data/idata space with the C51 toolchain. You would probably be best to address the question directly to Keil support for an authoratitive answer.
Sadly though some contributors are not well known for their ability to read and understand a post
Mr. smoked sardine: you should, by now, have noticed how many threads have gone astray becuse somebody "understood a post". Then, on the other hand, maybe you are just too busy looking for ways to criticize.
anyhow, I'm glad you got another chance to get your bile out and am greatly surprised that you, for the first time, actually included something marginally useful for the OP
you should, by now, have noticed how many threads have gone astray becuse somebody "understood a post".
Actually, this thread was going astray because you hadn't read and/or understood a perfectly clear post.
There were two pieces of information clearly stated in the OPs first post which, in your haste to criticise both his choice of processor and his posting ability, you completely ignored.
sprat /spræt/ Pronunciation Key - Show Spelled Pronunciation[sprat] Pronunciation Key - Show IPA Pronunciation â€"noun, plural sprats, (especially collectively) sprat for 1. 1. a species of herring, Clupea sprattus, of the eastern North Atlantic. 2. a small or inconsequential person or thing.
both defintions fit
1. a species of herring, Clupea sprattus, of the eastern North Atlantic. 2. a small or inconsequential person or thing.
...and neither definition is 'smoked sardine'. Nice to see you consulting a proper source for a change rather than grandma's recipe book.
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