This clock works with Japanese radio clock system so the country out of Japan can not use this equipment just as it is. Please arrange in the system in your country by yourself referring to the contents to carry on these pages.
Consideration of a program address
In PIC16F series, the maximum address range which an instruction can operate directly is from 0 to 2047. PIC16F873 has 4K words program memory. Therefore, in order to access the program memory after 2048, it is necessary to set up the contents of the PCLATH register each time.
In PIC16F series, a program memory is managed by 2K words unit. This unit is called a page. The page of a program memory is specified by the 3rd and 4th bit of a PCLATH register.
In order to jump by GOTO or CALL exceeding each page, LGOTO or LCALL is used.
These are called Directive. These are not the instruction of PIC16F. It is automatically changed as follows when assembling a source code with these directions. This is the example which jumps from page 0 to INIT (the address in the page : h'3FE") of page 1.
Source code
LGOTO INIT
Assembling result
158A BSF PCLATH,3
120A BCF PCLATH,4
2BFE GOTO h'3FE'
You can see that it set "1" to the 3rd bit of PCLATH and the page is changed to page 1.
It is automatically processed in LGOTO as mentioned above if jumping only like GOTO.
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