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Andrew_G
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Joined: 18/10/2016
Location: Australia
Posts: 910

Posted: 11:53pm 24 Oct 2026

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Hi There,
I am trying to use my PC3 to access OpenWeather forecasts.
I'm using version 7.000008 HDMIUSB.
I've done it before with my PicoW1 which reliably gets 8, 4-hr forecasts (using older firmware versions).
In the code below (only a test snippet), by varying the value of CNT, I 'rarely' get 8, 'sometimes' 4, and 'usually' 2 forecast periods. It does vary!
When it fails it has omitted some of the lead-in text and text after "ground_lev".
I've previously used much smaller buffer for m%() but increasing it here 'appears' to help??
The PAUSEs dont seem to do anything?

Any suggestions/better code?

Cheers,

Andrew

'Get_Forecast Check v2.bas

OPTION EXPLICIT
OPTION DEFAULT NONE

Dim Integer TZone = 10, DST = 1, II
DIM string ID$ = "7932628" 'Kew East
Dim string APIKEY$ = "****. . ."
dim integer CNT = 8 'No of x4 hr time periods requested in forecast. 8 = 24hrs
Dim INTEGER m%(2048*3) 'm% should be a multiple of 8
Dim string b$

b$ = "GET /data/2.5/forecast?id="+ID$+"&APPID="+APIKEY$+"&units=metric"+"&cnt="+STR$(CNT)+Chr$(10)+Chr$(13)

longstring CLEAR m%()

WEB NTP Tzone+DST,"au.pool.ntp.org"

pause 1000

WEB OPEN TCP CLIENT "api.openweathermap.org", 80

WEB TCP CLIENT REQUEST b$,m%()

pause 1000
LongString print m%()
print
print "Site ";JSON$(m%(),"city.name")
print "Sunset ";json$(m%(),"city.sunset")
print "CNT ";json$(m%(),"CNT")
print

for II = 0 to 8
print json$(m%(),"list["+str$(II)+"].wind.deg")
next II

WEB CLOSE TCP CLIENT

end

Edited 2026-10-25 10:16 by Andrew_G

TassyJim

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Joined: 07/08/2011
Location: Australia
Posts: 6632

Posted: 05:42am 25 Oct 2026

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I get a json string 3534 bytes long.

If you take the last 1460 bytes and move them to the beginning of the string, you will have working json data

It looks like packets out of order or a ring buffer got lost.

Tested with WEBMITE and HDMIWEB V7 RC5

Jim

VK7JH
MMedit

Andrew_G
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Joined: 18/10/2016
Location: Australia
Posts: 910

Posted: 06:39am 25 Oct 2026

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Hi Jim,
Thanks. Are you able to capture a LONGSTRING PRINT of a typical full lot of data.
(MMCC can help . . .)
I'm using similar hardware with RC8.

Cheers,

Andrew

TassyJim

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Joined: 07/08/2011
Location: Australia
Posts: 6632

Posted: 07:08am 25 Oct 2026

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Yes , provided you have wordwrap on, MMCC can capture the full longstring.

Email sent.
First string is with the wrong sequence.

second string has it 'fixed' but not tested.

Jim

VK7JH
MMedit

TassyJim

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Joined: 07/08/2011
Location: Australia
Posts: 6632

Posted: 07:22am 25 Oct 2026

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'Get_Forecast Check v2.bas

OPTION EXPLICIT
OPTION DEFAULT NONE

Dim Integer TZone = 10, DST = 1, II
DIM string ID$ = "7932628" 'Kew East
Dim string APIKEY$ = "xxxxxxxxxxxxxxxxx"
dim integer CNT = 8 'No of x4 hr time periods requested in forecast. 8 = 24hrs
Dim INTEGER m%(576*8) 'm% should be a multiple of 8
dim integer k%(576*8)
Dim string b$

b$ = "GET /data/2.5/forecast?id="+ID$+"&APPID="+APIKEY$+"&units=metric"+"&cnt="+STR$(CNT)+Chr$(10)+Chr$(13)

longstring CLEAR m%()

WEB NTP Tzone+DST,"au.pool.ntp.org"

pause 1000

WEB OPEN TCP CLIENT "api.openweathermap.org", 80
'print b$
WEB TCP CLIENT REQUEST b$,m%() ',3000

pause 1000
print llen(m%())
LongString print m%()
print
longstring right k%(),m%(),1460
longstring concat k%(),m%()

print "Site ";JSON$(k%(),"city.name")
print "Sunset ";json$(k%(),"city.sunset")
print "CNT ";json$(k%(),"CNT")
print

for II = 0 to 8
print json$(k%(),"list["+str$(II)+"].wind.deg")
next II

WEB CLOSE TCP CLIENT
memory
end

Crude fix to reorder the json string

Jim

VK7JH
MMedit

TassyJim

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Joined: 07/08/2011
Location: Australia
Posts: 6632

Posted: 08:34pm 25 Oct 2026

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Further information.
This morning every second run works as it should.
The next run through needs the adjustment to the json string.

Jim

VK7JH
MMedit

Andrew_G
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Joined: 18/10/2016
Location: Australia
Posts: 910

Posted: 09:26pm 25 Oct 2026

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Hi Jim,
Don't waste precious sunshine but:
- I'm seeing inconsistencies too
- If you take my original code and change CNT to 2 it works every time
- I've played with the size of m%() - seems to not make any difference.

Added:
- The LLEN is consistently 3492
- On a standalone Webmite2 with older firmware it works as intended, ie with CNT = 8

Cheers,

Andrew
Edited 2026-10-26 08:16 by Andrew_G

TassyJim

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Joined: 07/08/2011
Location: Australia
Posts: 6632

Posted: 11:32pm 25 Oct 2026

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With CNT = 2, the packet length is 1020 so it fits into one TCPIP packet. That is why it works every time.

VK7JH
MMedit

Andrew_G
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Joined: 18/10/2016
Location: Australia
Posts: 910

Posted: 03:56am 26 Oct 2026

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OK Folks,
Thanks to Jim it appears that the following code works on a PC3.
BUT why is it happening?
(It works without the test on 2040 WebMite running 7.000007)

Cheers,

Andrew

'Get_Forecast Check JH AGv2.bas
'Works on "WebMite" v1 2040 v7.000007
'Now works on PC3 using the test for "{"cod":200"

OPTION EXPLICIT
OPTION DEFAULT NONE

Dim Integer TZone = 10, DST = 1, II
DIM string ID$ = "7932628" 'Kew East

Dim string APIKEY$ = "xxxxxxxxxxxxxxxxx"

dim integer CNT = 8 'No of x4 hr time periods requested in forecast. 8 = 24hrs
Dim INTEGER m%(576*8) 'm% should be a multiple of 8
dim integer k%(576*8)
Dim string b$

b$ = "GET /data/2.5/forecast?id="+ID$+"&APPID="+APIKEY$+"&units=metric"+"&cnt="+STR$(CNT)+Chr$(10)+Chr$(13)

longstring CLEAR m%()
longstring CLEAR k%() '+ANG

WEB NTP Tzone+DST,"au.pool.ntp.org"

pause 1000

WEB OPEN TCP CLIENT "api.openweathermap.org", 80
WEB TCP CLIENT REQUEST b$,m%() ',3000

pause 1000
print llen(m%())
LongString print m%()

'Test for "{"cod":200"
'r$ = LGETSTR$(array%(), start, length) Returns part of a long string as a normal string.
if LGETSTR$(m%(),1,12) = "{"+chr$(34)+"cod"+chr$(34)+":"+chr$(34)+"200"+chr$(34) then
' i.e. it is OK as is
print
print "Copying m%()) to k%():"
longstring copy k%(), m%()
else 'Use Jim's approach
print
print "Concatinting last 1460 to the front"
longstring right k%(),m%(),1460
longstring concat k%(),m%()
End if

print
print "Resulting k%():"
longstring Print k%() '+ANG

print "Site ";JSON$(k%(),"city.name")
print "Sunset ";json$(k%(),"city.sunset")
print "CNT ";json$(k%(),"CNT")
print

for II = 0 to 8
print json$(k%(),"list["+str$(II)+"].wind.deg")
next II

WEB CLOSE TCP CLIENT
memory
end

Edited 2026-10-26 13:58 by Andrew_G

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