Trouble with MAX232
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Hi all,
I am trying to set up a MAX232 to debug my serial communications between my BSII
and a PIC16F84, however I am having trouble with a hardware problem...
I have set my MAX232 up exactly as the datasheet says for a typical
configuration (using 4 1uf caps) and have connected the stamp output pin
directly to one of the MAX232 TTL inputs.
I have written a little bit of pbasic that simply prints out the ASCII character
'A' over and over... however when I start up my terminal program I get the
following:
I am trying to set up a MAX232 to debug my serial communications between my BSII
and a PIC16F84, however I am having trouble with a hardware problem...
I have set my MAX232 up exactly as the datasheet says for a typical
configuration (using 4 1uf caps) and have connected the stamp output pin
directly to one of the MAX232 TTL inputs.
I have written a little bit of pbasic that simply prints out the ASCII character
'A' over and over... however when I start up my terminal program I get the
following:
Comments
held low and pulled high by data, and converts it to a PC-compatible RS-232
signal which is held high and pulled low by data. You need to get the data
coming out of the Stamp the right way and it should work.
Original Message
I am trying to set up a MAX232 to debug my serial communications between my
BSII and a PIC16F84, however I am having trouble with a hardware problem...
I have set my MAX232 up exactly as the datasheet says for a typical
configuration (using 4 1uf caps) and have connected the stamp output pin
directly to one of the MAX232 TTL inputs.
I have written a little bit of pbasic that simply prints out the ASCII
character 'A' over and over... however when I start up my terminal program I
get the following:
thanks for your replys!
Peter wrote:
<snip>
You probably have the incorrect constant for the baudrate.
You must use the value for connect through line driver which
Is different than the value for port 16
Check the manual.
<snip>
Doh! I HAD read the manual, however on going back just now to referrence the
page I noticed what you mean by different values for non-inverted line
driver.... changed the value and BAM! it works :-)
Thanks so much for your help,
kind regards,
James Fitzsimons
You probably have the incorrect constant for the baudrate.
You must use the value for connect through line driver which
Is different than the value for port 16
Check the manual.
Regards peter
Oorspronkelijk bericht
Van: James Fitzsimons [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=eSbxm2gWKPVgEYJOxO3213v_8DaVtTKOLTz7uzxcRHTIeawqtCSX7Ms9JHqAaPLqrrXKPkg3v0tefogRdaI]jamesfit@p...[/url
Verzonden: woensdag 7 november 2001 1:14
Aan: basicstamps@yahoogroups.com
Onderwerp: [noparse][[/noparse]basicstamps] Trouble with MAX232
Hi all,
I am trying to set up a MAX232 to debug my serial communications between my
BSII and a PIC16F84, however I am having trouble with a hardware problem...
I have set my MAX232 up exactly as the datasheet says for a typical
configuration (using 4 1uf caps) and have connected the stamp output pin
directly to one of the MAX232 TTL inputs.
I have written a little bit of pbasic that simply prints out the ASCII
character 'A' over and over... however when I start up my terminal program I
get the following:
I use the following constants in my programs using the MAX232 (BS2SX)
'baudrate definitions for bs2sx (through line driver)
E71_1200 con 10255
E71_2400 con 9213
E71_4800 con 8692
E71_9600 con 8432
E71_19200 con 8302
E71_38400 con 8237
N81_1200 con 2063
N81_2400 con 1021
N81_4800 con 500
N81_9600 con 240
N81_19200 con 110
N81_38400 con 45
Regards peter
Oorspronkelijk bericht
Van: James Fitzsimons [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=FutfLeDX5TJz2EzM-EmRGWcnG08XWAPRIvtwCSo_s5cPNFjwrg1sJQG3ajRMQL9YS3LsfD8nnljM9vEpNvCmD0IA]jamesfit@p...[/url
Verzonden: woensdag 7 november 2001 1:14
Aan: basicstamps@yahoogroups.com
Onderwerp: [noparse][[/noparse]basicstamps] Trouble with MAX232
Hi all,
I am trying to set up a MAX232 to debug my serial communications between my
BSII and a PIC16F84, however I am having trouble with a hardware problem...
I have set my MAX232 up exactly as the datasheet says for a typical
configuration (using 4 1uf caps) and have connected the stamp output pin
directly to one of the MAX232 TTL inputs.
I have written a little bit of pbasic that simply prints out the ASCII
character 'A' over and over... however when I start up my terminal program I
get the following: