New Limited 12-bit Core Support

PicBasic Pro version 2.40 adds limited support for all the 12-bit core PICmicro microcontrollers. The reason the support is limited is that the resources on the 12-bit core devices are very limited. Some of these limits include only a two-level hardware stack and very small amounts of general purpose RAM memory. The code page size is also small at 512 bytes. There is also a limitation that calls and computed jumps can only be made to the first half (256 words) of any code page. These limitations have made it necessary to eliminate some compiler commands and modify the operation of some others.

While many useful programs can be written for the 12-bit core PICmicro MCUs using the PicBasic Pro Compiler, some applications will not be suited for these devices. Choosing a 14- or 16-bit core device with more resources will, in many cases, be the best solution.

Commands that are not supported for the 12-bit core PICmicro MCUs:

Command	Reason
Adcin	No internal ADCs
Data	No on-chip EEPROM
Dtmfout	Not enough RAM or stack
Eeprom	No on-chip EEPROM
Freqout	Not enough RAM or stack
Hpwm	No hardware PWM
Hserin	No hardware serial port
Hserout	No hardware serial port
On Interrupt	No Interrupts
Read	No on-chip EEPROM
Readcode	No flash devices
Resume	No Interrupts
Serin2	Not enough RAM or stack
Serout2	Not enough RAM or stack
USBIn	No USB devices
USBInit	No USB devices
USBOut	No USB devices
Write	No on-chip EEPROM
Writecode	No flash devices
Xin	Not enough RAM or stack
Xout	Not enough RAM or stack

Trying to use these commands with 12-bit core devices will result in numerous errors. If you must use one of these commands, choose a 14- or 16-bit core device with more resources.

Commands that have had their operation modified are: Debug, Debugin - The Serin2 and Serout2 modifiers are not supported for these commands because of memory and stack size limits. Lcdout - The Serout2 modifiers are not supported for this command because of memory and stack size limits. OWIn, OWOut - The Rep, Skip and Str modifiers are not supported for these commands because of memory and stack size limits. Serout - The open drain modes are not available due to TRIS register constraints.