From 94a22dc399fc64e53d2937b8048d4a2d151a1d63 Mon Sep 17 00:00:00 2001 From: phl0 Date: Wed, 16 Nov 2016 13:29:27 +0100 Subject: [PATCH] Add wiring info to README.HD44780 --- README.HD44780 | 39 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+) diff --git a/README.HD44780 b/README.HD44780 index 5364e28..349fe73 100644 --- a/README.HD44780 +++ b/README.HD44780 @@ -6,6 +6,45 @@ http://wiringpi.com/download-and-install/ which must be installed in all cases. The HD44780 in 4-bit mode is probably the most common connection method and wiring details can be found at http://wiringpi.com/dev-lib/lcd-library/ +The setup that is commonly used for MMDVM is the 4-bit connection that is also +documented within wiringPi. The HD44780 displays have a standardized 16-pin +connector (14 pins if without backlight). The pin numbers on HD44780 refer to +this standard numbering. + +The pin numbers on Raspberry Pi side are the physical pin numbers of the GPIO +pin header, in brackets the wiringPi pin number as these are referred to in the +MMDVM.ini file. + +The wiring ist as follows: + + HD44780 pin Raspberry Pi GPIO + GND 1 -------- 6 GND + VCC 2 -------- 2 +5V + V0 3 -------- Trimmer between +5V and GND for contrast + RS 4 -------- 26 CE1 (11) + RW 5 -------- 6 GND + E 6 -------- 24 CE0 (10) + D0 7 + D1 8 + D2 9 + D3 10 + D4 11 -------- 11 GPIO0 (0) + D5 12 -------- 12 GPIO1 (1) + D6 13 -------- 13 GPIO2 (2) + D7 14 -------- 15 GPIO3 (3) + GND 15 -------- 6 GND + VCC 16 -------- 2 +5V + +The relevant part in the MMDVM.ini is like outlined below. + +[HD44780] +Rows=4 +Columns=20 + +# For basic HD44780 displays (4-bit connection) +# rs, strb, d0, d1, d2, d3 +Pins=11,10,0,1,2,3 + To compile MMDVMHost with support for the HD44780 use the following commands. # cp Makefile.Pi.HD44780 Makefile