Post by thread:14 bits and only 3FFF

I am a little confused. I have just read the programming data sheet for the 16C84 where it states that when you read the retrieved data from the program memory it is in a 14-bit format. However if I read an empty PIC the word is 3FFF which requires only 13 bits. A 14-bit word would give me a maximum of 7FFF. Can sombody explain this please? Have a happy Christmas

11 1111 1111 1111 = 14 bits 3 F F F > However if I read an empty PIC the word is 3FFF which requires only 13 bits. > A 14-bit word would give me a maximum of 7FFF. ----------------------------------------------------------------------- Larry P. Thomas wa0gwa voice : 1 913 888-0282 Krell Technologies fax : 1 913 782-9359 8960 Bond pager : 1 816 989-HELP Overland Park, KS www : http://www.krell.com 66214-1764 e-mail : //spam_OUTlpthomasTakeThisOuTwinning-edge.com -----------------------------------------------------------------------

part 0 574 bytes -----Original Message----- From: Francesco Cembrola [SMTP:.....FcembrolaKILLspam@spam@BTINTERNET.COM] Sent: Tuesday, December 23, 1997 4:06 PM To: PICLISTKILLspamMITVMA.MIT.EDU Subject: 14 bits and only 3FFF I am a little confused. I have just read the programming data sheet for the 16C84 where it states that when you read the retrieved data from the program memory it is in a 14-bit format. However if I read an empty PIC the word is 3FFF which requires only 13 bits. A 14-bit word would give me a maximum of 7FFF. Can sombody explain this please? Have a happy Christmas

-----Original Message----- From: Francesco Cembrola <.....FcembrolaKILLspam.....BTINTERNET.COM> To: EraseMEPICLISTspam_OUTTakeThisOuTMITVMA.MIT.EDU <PICLISTspam_OUTMITVMA.MIT.EDU> Date: Tuesday, December 23, 1997 6:16 PM Subject: 14 bits and only 3FFF >However if I read an empty PIC the word is 3FFF which requires only 13 bits. A 14-bit word would give >me a maximum of 7FFF. 'H'3FFF='B'11-1111-1111-1111 - 14 bit 'H'7FFF='B'111-1111-1111-1111 - 15 bit Gennady Palitsky Jefferson Audio Video Systems @spam@gennadypKILLspammainlink.net

1 bit 2^1 =2 =2h 2 bit 2^2 =4 =4h 3 bit 2^3 =8 =8h 4 bit 2^4 =16 =10h 5 bit 2^5 =32 =20h 6 bit 2^6 =64 =40h 7 bit 2^7 =128 =80h 8 bit 2^8 =256 =100h 9 bit 2^9 =512 =200h 10 bit 2^10 =1024 =400h 11 bit 2^11 =2048 =800h 12 bit 2^12 =4096 =1000h 13 bit 2^13 =8192 =2000h 14 bit 2^14 =16384 =4000h these are the number of combinations, 0 included this gives 3FFFh as a maximum number Peter {Original Message removed}

> >I have just read the programming data sheet for the 16C84 where it states >that when you read >the retrieved data from the program memory it is in a 14-bit format. > >However if I read an empty PIC the word is 3FFF which requires only 13 >bits. A 14-bit word would give >me a maximum of 7FFF. > >Can sombody explain this please? The DATA bus is 14 bits, the ADDRESS bus determines the program memory space. There is another address and data bus for the data memory, but that's a different question. Ray Gardiner Technical Director DSP Systems KILLspamrayKILLspamdsp-systems.com private email to:- RemoveMErayTakeThisOuTnetspace.net.au http://www.dsp-systems.com