>>> example.let 26 30 September 1991
>sm10
>tm3
>bm4
>-------!-------!-------!-------!-------!-------!-------!---R
                                        F. Hargreaves,
                                        1 Henley Road,
                                        Lee Park
                                        London SE21.
                                        
                                        071 123 4567

                                        &sys_date&












This demonstrates the use of Macro Mailmerging.

If 300 letters are to be printed with a different name and 
address on the first page, then each letter must be sent 
separately - the letter must be sent 300 times.

There is however a faster way, which we will call Macro 
Mailmerging. This means that the letter is downloaded once 
only to the Laserjet as a Macro. To print a Merge Letter, all 
we have to send is each name and address, followed by the 
control code to invoke the Macro that prints the letter.

Some figures: a letter might be 3K long, so 300 letters would 
be 900 Kbytes. To this, we must add 300 addresses, about 100 
bytes each, giving 30 kBytes. Grand Total, 930 Kbytes.

Using the Macro method, we send the letter once (3 Kbytes). 
The address plus control codes might be 114 bytes each, total 
34 kBytes. Grand Total - 37 Kbytes.

Clearly, there is a great reduction in the amount of data 
being sent; a small buffer can easily hold it all, so the 
computer is returned to the user in about a minute. Using the 
normal method, the computer would be out of use for almost 
the whole of the 40 minutes needed to print the letters.

Using a serial printer interface, there will be a very large 
improvement. The 3 Kbyte letter will take 8 seconds to send 
at 9600 Baud; normally, it has to be sent 300 times. This is 
40 minutes, which will double the total printing time.

                       Yours sincerely,



                       F.Hargreaves.