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.
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.
gives an indication
oh glory day when we can post based on knowledge, not 'indications'
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).
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.
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