interface thermal printer with 8051
SUMMARY


Link to 170+ page manual below
See pseudo code for writing to printer below
BUT see note at end of this answer - you printer may be a serial and not parallel interface  version !!!




You can download a complete Citizen CBM1000 printer manual here . This provides much useful information. (173 pages in English  + about 40 in German.

You description of the interface protocol sounds adequate to allow data transfer IF you interpret it slightly differently that it is written.   

Can you please provide more details about what difficulties you are having.



Here is how I would interpret the data writing instructions.
 NB this interpretation MAY be wrong.


Initialisation
Set strobe pin high
For each data character follow the following steps.
Step1: 
Write data to data port.
Check busy line.
If      busy line is set, repeat step 1.
else, if busy line is not set perform step 2. 
Step 2
Set strobe pin low
Wait 5+ microseconds
Set strobe pin high.




VERY IMPORTANT - (This note can be rewritten in due course to make it a general comment)

IF your printer DOES have a DB25 connector it is probably a serial "RS232" version. 

Both parallel and serial versions exist - see the manual link above. 

If it is a serial version then the parallel protocol that you have provided is probably not the correct one to use. 

Please provide more identifying information about your printer to help establish whether it is a serial or parallel port version.