Is there a 4 by 32 character LCD?

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Pommie

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The Hitachi chip that all the cheap character LCD displays are based on can address 128 character locations. This means it can drive a 4 line by 32 column display. Does anyone make such a display? Biggest I've seen is 4x20 and some dual chip displays.

Thanks,

Mike.
Edit, looks like the chip can access a max of 80 characters.
 
I've seen 4x40 displays with two Hitachi controllers (and 2 enable pins) but I (wrongly) assumed that as the second line was 64 counts ahead of the first line that the controller could drive 32 characters per line or even 2 lines of 64 characters.

Mike.
 
What do you need it for.... A Toshiba 240x64 in text mode does 32 x 8 characters
 
I don't actually need it but am currently writing code for an I²C backpack and wasn't sure if I needed to consider it or not.

Mike.
Edit, how quick is the Toshiba board? The current I²C backpack take around 1mS per character - or 80mS to refresh a 20x4 display.
 
So!! Why so fast... I update my display 10 times a second and that's too fast.. Using a pic18f I get a full screen refresh around 75mS wit a 20Mhz crystal.. You can buy a serial backpack for the Toshiba..
 
I was trying to write a scrolling menu using an I²C LCD and it was just too unresponsive. When you spin a rotary encoder and nothing happens, you realise that 80mS is far too slow. On my 3D printer the rotary encoder is super responsive and that's what I want to imitate. When you have to write two bytes just to toggle the enable pin it just gets too slow.

Mike.
 
If you use a nibble bus and toggle a pin to enable, yes!! Four writes per character... You need the 16bit SPI chip.. Very fast.. especially when you get the SPI up to 10 ~ 12Mhz.. I2C is sill only 400Khz, It'll probably run faster, but still no match for SPI..
 
Are you updating all 80 characters every time or just the characters that need to be changed?
 
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