BLOCK BUFFER SIZE, BUFSIZE and SD ramps!!

Hi,

I am using Marlin with ramps 1.4 and arduino, and I want to know the max buffer when we are reading the SD card.
I found BLOCK BUFFER SIZE defined on configuration_adv.h, but I cannot understand the difference with BUFSIZE!!

Thank you

You can modify your own messages for a limited amount of time chik (if you think it is not clear).

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Most of my technical comments should be correct, but is THIS one ?
Anyway, as a rule of thumb, always double check what people write.

I post a new message, where I detail my problem : [forums.reprap.org]

I am sorry!!

It reads 75% of the buffer and then loads a new one.

Thank you uncle_bob for your response.

But, if we send just one command, it will read it directly. It does not wait 75% of the buffer. I am searching for the loop, where it wait to reach the 75% of the buffer, and I didn't find it.
I don't understand realy what does it do, when we send a complete Gcode through Pronterface. Please help me

Quote
chik
Thank you uncle_bob for your response.

But, if we send just one command, it will read it directly. It does not wait 75% of the buffer. I am searching for the loop, where it wait to reach the 75% of the buffer, and I didn't find it.
I don't understand realy what does it do, when we send a complete Gcode through Pronterface. Please help me

I don't know where the 75% comes from, and I am not sure exactly what you are trying to find out.

However, the code is quite straightforward. BUFSIZE is the size of the unparsed line buffer "cmdbuffer". BLOCK_BUFFER_SIZE is the size of the movement block queue "block_buffer". Of course, not all Gcode commands result in a move.

get_command() reads the next command, either from serial or the SD card. In the case of G1, plan_buffer_line() will be called to place the move into the block buffer. if the buffer is full, that function loops until there is space. The stepper module frees blocks when they are finished by calling plan_discard_current_block().

Marlin, like most other firmwares, blocks comms when the move buffer is full. It doesn't have to be that way, it's quite easy to code it differently and you don't need a real time OS to do it, but that is the way they are.

Edited 1 time(s). Last edit at 11/08/2013 04:25PM by bobc.

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Hi bobc,

Sorry for the late reply. I worked on another thing than the Marlin!
Last week, I sew this part, and it seems exactly as you said!

plan_buffer_line() will be called to place the move into the block buffer.
plan_discard_current_block() remove the command when it is finished!!

All this function are in interruption on stepper.c

Thank you!!