DIYstompboxes.com
Welcome,
Guest
. Please
login
or
register
.
Did you miss your
activation email
?
1 Hour
1 Day
1 Week
1 Month
Forever
Login with username, password and session length
News:
SMF for DIYStompboxes.com!
|HOME|
|DIY FAQ|
|GEO FAQ|
|Debugging Page|
|Links|
|Schematics|
|Wiki|
|Layouts Gallery|
|STORE|
|AMPAGE|
|GEOFEX|
|AMZ|
Home
Help
Login
Register
DIYstompboxes.com
»
DIY Stompboxes
»
Digital & DSP
»
PIC Program Memory question
« previous
next »
Print
Pages: [
1
]
Go Down
Author
Topic: PIC Program Memory question (Read 4090 times)
burningman
Great Contributor!
Posts: 207
Total likes: 0
PIC Program Memory question
«
on:
March 27, 2009, 08:38:57 PM »
The 16F887A datasheet describes the chip as having 8k x 14words
Can someone explain this a bit clearer? I'm writing a program, pretty sure I'm not up to that limit
but unsure what it really means.
Thanks.
Logged
iaresee
Awesome!
Posts: 652
Total likes: 0
Ian C.
Re: PIC Program Memory question
«
Reply #1 on:
March 27, 2009, 09:57:04 PM »
A word is the smallest size of instruction you can address in memory. This is different than the smallest size of memory you can address in your program. In your PIC words are 14 bits if I'm reading that correctly. So you've got 8k x 14 bits = 14 KBytes of program space available to you in 14 bit chunks. Basically you can store a program in on-chip memory that's got 8000 instructions in it.
Logged
ElectricDruid
Awesome!
Posts: 3660
Total likes: 1903
Tom W.
Re: PIC Program Memory question
«
Reply #2 on:
May 14, 2009, 11:08:56 AM »
iaresee is spot on.
You've got 8096 instructions-worth of program space. Each instruction is 14-bits, so in total that's 14KBytes. Mosty, though, you'll be thinking about it in terms of instructions, so it's just over 8000 instructions.
T.
Logged
SUPPORTER
Electric Druid.net: Synth and Pedal DIY with interesting stuff!
MoltenVoltage
Awesome!
Posts: 743
Total likes: 3
Cascade Range, Oregon
Re: PIC Program Memory question
«
Reply #3 on:
May 17, 2009, 12:44:09 AM »
If you need to see how much memory your program uses, just view the Program Memory in MPLAB after you Build. All the unused memory will be at the bottom as RETLW.
Logged
MoltenVoltage.com
for PedalSync audio control chips - make programmable and MIDI-controlled analog pedals!
Print
Pages: [
1
]
Go Up
« previous
next »
DIYstompboxes.com
»
DIY Stompboxes
»
Digital & DSP
»
PIC Program Memory question