Size of Input Buffer in Serial Terminal

A

Absolute_Beginner

Member
OK So I'm probably not using the PE's Terminal for it's proper purpose...I'm presently (temporarily I hope) using it to check the contents of my 24LC16B EEPROM so I'm inspecting a few kbytes of data sent by sertxd.

When I try to send more than a certain amount (it varies, I'm not sure why because I'm always sending the same number of bytes [numerical values and sonstant length strings, i.e. white spaces] the number of numbers retained in the I/P of the terminal (or copied if I use the copy I/P buffer option) is truncated and I lose the first however many data bytes (several hundred bytes).

If I write 6 bytes per line through 2048 lines (about 12K) I lose the ~ the first 1400 lines or so. (The way I overcame this problem, a temporary fix, was to modify my code each time and run it three times, collecting about 1/3 at once; in fact the I/P buffer seems to hold the first 1000 lnes without any problem...).

I assume this is me trying to load too much data into the I/P buffer of the Terminal...if so, what the size of this buffer ? I can't find it in parts 1&2 of manual (although it mifght be there !) nor have I looked in absolutely every post in the forum.

Mght be useful for some folks if someone knows the size of O/P buffer too.

AB
24.June.2011

PS code available if needed
 
W

westaust55

Moderator
Past information from Technical was:
After 10,000 characters have been received the first 8,000 are deleted, leaving the latest 2,000 and space for another 8,000!

So if you want to save data using this feature upload in 'batches' under 10,000 characters long.
Click to expand...
Do not know if this situation has change in recent times.

There was at the time a suggestion from hippy to delete just 2000 bytes and retain 8000 bytes.
 
A

Absolute_Beginner

Member
Thanks again.
I obviously didn't look carefully enough through the forum, I don't really like starting unnecessary new threads..
You speak in "characters" and I'm writing data in bytes...does this limit pertain to number of characters printed on I/P screen of the terminal thn ? there's a difference in size between a '1' and '137' allthough they are they both 1 byte numbers ?

AB
24.June.2011
 
E

eclectic

Moderator
Another possibility is
Brays terminal.

simple prog

Code: 
#picaxe 18M2
setfreq m32

for w0 = 0 to 16000
sertxd(#W0," ")
next
Pics show that all 16000 values are retained.


e
 

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M

MartinM57

Moderator
Generally +1 for Brays Terminal - but it's not integrated into the PE so you have to keep connecting it to COM1: (or whatever), restart the PICAXE, read the output in Bray's, disconnect from COM1:, go back to PE to change code and reprogram...and repeat
 
E

eclectic

Moderator
50 000 retained

This works

Code: 
#picaxe 18M2
setfreq m32

for w0 = 0 to 50000
sertxd(#W0," ")
next
Addit
And I agree with Martin.
e
 
J

jtcurneal

Senior Member
Martin57 said

"Generally +1 for Brays Terminal - but it's not integrated into the PE so you have to keep connecting it to COM1: (or whatever), restart the PICAXE, read the output in Bray's, disconnect from COM1:, go back to PE to change code and reprogram...and repeat"

I have uploaded up to 65,000 bytes from a 24LC512 EEPROM data logger with a 18M2 to a PC. I used PUTTY on the PC to log the data to a file. The 18M2 converted the raw data into a comma delimited format so I can inport the data into excel or a database. Works like a charm.

Joel
 
A

Absolute_Beginner

Member
Thanks Joel.

I wasn't going to do a google search because I did not want lots of irrelevant results about 'a pliable substance made with linseed oil' or links to builders merchants website telling me where I could buy the aforementioned substance :)

In fact I didn't even think of looking in the PICAXE forum. I have tried to use various terminal programs before and I couldn't get ANY of them (e.g., Kermit, Portmon [I think it was called]) to work. Kermit I couldn't even start, and despite many attempts to remove it from my PC there are still remnants on my HDD and corrupting my registry no doubt.

AB
26.June.2011
 
J

jtcurneal

Senior Member
I first found about PuTTY here on this forum. There are other terminal programs out there, but this one has worked for me.

Joel
 
I

inglewoodpete

Senior Member
Absolute_Beginner said:
Thanks Joel.

I wasn't going to do a google search because I did not want lots of irrelevant results about 'a pliable substance made with linseed oil' or links to builders merchants website telling me where I could buy the aforementioned substance :)
AB
Click to expand...
I don't know if you're being serious or not. By doing a bit of simple filtering with google, you can usually shorten your list like search for putty serial communications download. There may have been 1,400,000 hits but guess what was at the top of the list?
 
W

westaust55

Moderator
Concur with IWP

Goggle got 57k Hits (as opposed to 1M4 hits) for me with same result = "first cab of the rank" with little evidence of Linseed based products
 
A

Absolute_Beginner

Member
I don't know how the 'Datalink' utility in the PE works, but adapting my code to use that (guided by the program generated by the Wizard) allows me to capture to file the contents of every byte in my 24LC16B and write the number of that byte's address [a sequential number between 0 and 2047), its block address and its byte address. :)

I guess it's just another terminal, or different use of one built in to terminal in PE.

AB
26.June.2011
 
W

westaust55

Moderator
The datalink (accessed by [F9] will accept up to 10,000 bytes bore data is truncated.
The 24lc16b only holds 2048 bytes of data so there will never be s problem
 
W

westaust55

Moderator
Start you Grimoire

Absolute_Beginner said:
@westaust55: how do you find this stuff out ? It's useful info though, for when I try to start to use the big chips (they've come....) :D

AB
28.June.2011
Click to expand...
Information is found by various methods, the main ones being:
1. Trolling through and reading the archives on this forum (then remembering what you have read for sort of instant recall at a later date)
2. Reading the datasheets for many many chips - This is my second time around in electronics as a hobby (first time there was no Internet, no forums, and for some years I lived on a small island around 2,500 km from the nearest electronics shop, so in summary there was no one else to ask a question thus reading, reading and more reading to learn was the only way).

If recollection is not optimal you may find starting your own "Grimoire" to keep important "incantations" at hand may be useful.
 
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