Rows I chose 7 because it can balance the letter, if some one takes 8 rows the letter will be slightly unbalanced.
Columns 32 is good for me. It can drive from two16 bit shift registers or from four 8 bit shift registers.
But this column number can be determine by the shift register used by the user.
For a 28 or 32 columns it can display 5 letters at a time taking 5 columns per letter + space between for letters.
Some thread on here a fellow wanted 3,200 LEDs (with 3,200 resistors!) Hey I don't mind soldering but there's a limit. Hey at 10ma each that's 32AMPs nice.
8x8 sounds good for a borderless cell size for general graphics as it can be done using a couple shift registers and addressed easily. If the primary use is text with more limited graphics something like the Hitachi LCD's use might be better which is 8X5 (the letters end up being 7x5 because the line space takes up a bit) You could also do 8X6 which would allow better graphics in a hitachi style way as the 6th column in a Hitachi display is always blank. Makeing the interface similar to a Hitachi display would give the bulk majority of electronics users an already well developed library of routines and plug in applications for it.
Some thread on here a fellow wanted 3,200 LEDs (with 3,200 resistors!) Hey I don't mind soldering but there's a limit. Hey at 10ma each that's 32AMPs nice.
lol, wait till I post some pictures of the fabled LED warning light I have been working on forever. I don't know how many hours I have in it soldering LEDs and resistors......
I'll vote for the 7x28 with RS232 or USB interface. Sounds like a really cool kit.
I would be interested in buying a 7x28 with rs232. USB would be great, too, but with RS232, we could use really old machines to run the display. I would like to hook it up to my really old compaq lte 4/50e (runs at 66mhz)
Are you going to have opensource software? That way it could be cross platform (linux, winblows, and...crapple)
I still think a basic 8X8 module would be best for flexibility and simplicity, you just have to make sure that it's modular and expandable. Maybe two types of modules, a master 'row' module that has an address latch enable, and a slave 'column' that just tacks onto the previous modules shift register overflow bit. You could toggle it using a clocked serial line and a couple control lines. Would give the greatest flexibility to the end user.
I still think a basic 8X8 module would be best for flexibility and simplicity, you just have to make sure that it's modular and expandable. Maybe two types of modules, a master 'row' module that has an address latch enable, and a slave 'column' that just tacks onto the previous modules shift register overflow bit. You could toggle it using a clocked serial line and a couple control lines. Would give the greatest flexibility to the end user.