Hello,
I'm trying to interface the Softbaugh SBLCDA4 with the MSP430FG437 that we're debugging with the USBFET430UIF tool. Looking at the schematic provided in SLAA458, we have the S0-S21 pins connected appropriately and COM0-COM4 connected. We have a resistor ladder of 680k resistors connected to R33, R23, R13, and a 1k resistor connected to R03 which is then grounded.
It doesn't appear to be powering on whatsoever. There are zero lit segments or flickering.Within the SLAA458 document, it reads:
"The voltages required for the LCD signals are supplied externally to pins R33, R23, R13, and R03. Using an equally weighted resistor divider ladder between these pins establishes the analog voltages."
On the schematic there is no indication of any external power to these ports. I attached an image of the resistor ladder from the schematic below.
This is the function in the code that appears to power the LCD:
void set_LCD(void)
{
volatile unsigned int i;
for(i=0;i<11;i++) // Clear LCD memory
{
LCDMEM[i] = 0x00;
}
/* Turn on the COM0-COM3 and R03-R33 pins */
P5SEL |= (BIT7 | BIT6 | BIT5 | BIT4 | BIT3 | BIT2);
LCDCTL = 0x7F; // Selected function: Analog generator on
// Low impedance of AG
// 4Mux active
// all outputs are Seg
// S0-S23 are LCD segment lines
BTCTL = BTFRFQ0; // Start Basic Timer 1s + LCD 64Hz
}
