basic display driver

[Dc2LightTech]

I need to display temperatures from -99.9 to 99.9 (with the leading digit blanked when the value is positive. I will be driving 10 serial displays and I need to assign the CS pin.

[BrentWilkins]

Thanks for reaching out. The specific issue you are commenting on here is unclear. If you have found a specific bug in our code, please let us know. Otherwise, if you are simply looking to modify the code for your personal project, we have an example sketch for changing the SPI settings here.

[Dc2LightTech]

thanks for the reply. when I used ProMini's the example code worked well. this was like 5 years ago. Now I only use Teency's and the example code mostly does not work. the new GitHub SPI Bus code for the displays from: https://github.com/sparkfun/Serial7SegmentDisplay don't have chip and stuff for example, the folloning code is not helpull in getting basic display operation S7S_EcampleSerial_Basic: ( I would like to display{-12.3}

/* 9-23-2012 Spark Fun Electronics Nathan Seidle

This code is public domain but you buy me a beer if you use this and we meet someday (Beerware license). Serial7Segment is an open source seven segment display. This is example code that shows how to display basic numbers on the display.

Note: This code expects the display to be listening at 9600bps. If your display is not at 9600bps, you can do a software or hardware reset. See the Wiki for more info:

http://github.com/sparkfun/Serial7SegmentDisplay/wiki/Special-Commands#wiki-baud

To get this code to work, attached an Serial7Segment to an Arduino Uno using the following pins: Pin 8 on Uno (software serial TX) to RX on Serial7Segment VIN to PWR GND to GND

*/

include

SoftwareSerial Serial7Segment(7, 8); //RX pin, TX pin int cycles = 0; void setup() { Serial.begin(9600); Serial.println("OpenSegment Example Code"); Serial7Segment.begin(9600); //Talk to the Serial7Segment at 9600 bps Serial7Segment.write('v'); //Reset the display - this forces the cursor to return to the beginning of the display } void loop() { cycles++; //Counting cycles! Yay! Serial.print("Cycle: "); Serial.println(cycles);

char tempString[10]; //Used for sprintf sprintf(tempString, "%4d", cycles); //Convert deciSecond into a string that is right adjusted //sprintf(tempString, "%d", cycles); //Convert deciSecond into a string that is left adjusted (requires digit 1 command) //sprintf(tempString, "%04d", cycles); //Convert deciSecond into a string with leading zeros //sprintf(tempString, "%4X", cycles); //Count in HEX, right adjusted //int negativeCycles = cycles * -1; //sprintf(tempString, "%4d", negativeCycles); //Shows a negative sign infront of right adjusted number //Note: This method works well as long as your number is less than or equal to 4 digits. //14422 will cause the display to wrap (5 digits) //-5766 will cause the display to wrap (5 digits) //To fix this, send a 'v' character or look at how to control the digit placement // https://github.com/sparkfun/Serial7SegmentDisplay/wiki/Basic-Usage#wiki-cursor Serial7Segment.print(tempString); //Send serial string out the soft serial port to the S7S delay(10); }

On Thu, Feb 9, 2017 at 2:13 PM, Brent Wilkins notifications@github.com wrote:

Thanks for reaching out. The specific issue you are commenting on here is unclear. If you have found a specific bug in our code, please let us know. Otherwise, if you are simply looking to modify the code for your personal project, we have an example sketch for changing the SPI settings here https://github.com/sparkfun/Serial7SegmentDisplay/blob/master/firmware/Serial%207-Segment%20Display/Arduino_Examples/S7S_Example_SPI_Settings/S7S_Example_SPI_Settings.ino .

— You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub https://github.com/sparkfun/Serial7SegmentDisplay/issues/21#issuecomment-278742239, or mute the thread https://github.com/notifications/unsubscribe-auth/AYOmc4us8PORerTsxaz6-3B8G_cqKDbGks5ra2VcgaJpZM4L8U79 .

[BrentWilkins]

I wasn't able to reproduce any issues with the code found in S7S_Example_Serial_Basic on a Teensy. I wired up the TX line on the Teensy (8) to the RX line in the display module. To display your example of "-12.3" I replaced the contents of loop() with the following code:

// Writing 4 digits each time. In this case no need to clear display.
Serial7Segment.print("-123");
Serial7Segment.write(0x77); // Decimal control command
Serial7Segment.write(0b00000100); // Turns on tenths decimal

In other cases you might want to send the reset command (RESET_CMD | 0x76 | 'v') first. This might be Serial7Segment.print("v-123"); for this case.

If you want to modify the firmware to handle numbers rather than ASCII characters and commands, take a look at the void SevSeg::DisplayString(const char*, byte) method found here. I replaced line 114 in the firmware myDisplay.DisplayString(display.digits, display.decimals); with myDisplay.DisplayString("-123", 4); to display -12.3.

Do you have our SevSeg library installed? If you have the original library that we forked, not ours, you will get errors such as error: 'class SevSeg' has no member named 'DisplayString'.

[Dc2LightTech]

could you send the entire code please. This code is SPI not I2C, right?

On Tue, Feb 14, 2017 at 4:20 PM, Brent Wilkins notifications@github.com wrote:

I wasn't able to reproduce any issues with the code found in S7S_Example_Serial_Basic on a Teensy. I wired up the TX line on the Teensy (8) to the RX line in the display module. To display your example of "-12.3" I replaced the contents of loop() with the following code:

// Writing 4 digits each time. In this case no need to clear display. Serial7Segment.print("-123"); Serial7Segment.write(0x77); // Decimal control command Serial7Segment.write(0b00000100); // Turns on tenths decimal

In other cases you might want to send the reset command (RESET_CMD | 0x76 | 'v') first. This might be Serial7Segment.print("v-123"); for this case.

If you want to modify the firmware to handle numbers rather than ASCII characters and commands, take a look at the void SevSeg::DisplayString(const char*, byte) method found here https://github.com/sparkfun/SevSeg/blob/master/src/SevSeg.cpp. I replaced line 114 in the firmware https://github.com/sparkfun/Serial7SegmentDisplay/blob/master/firmware/Serial%207-Segment%20Display/Serial_7_Segment_Display_Firmware/Serial_7_Segment_Display_Firmware.ino myDisplay.DisplayString(display.digits, display.decimals); with myDisplay.DisplayString("-123", 4); to display -12.3.

Do you have our SevSeg library installed? If you have the original library that we forked, not ours, you will get errors such as error: 'class SevSeg' has no member named 'DisplayString'.

— You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub https://github.com/sparkfun/Serial7SegmentDisplay/issues/21#issuecomment-279839552, or mute the thread https://github.com/notifications/unsubscribe-auth/AYOmc-lrQodUAynRQU2MSrvXaL77eZQtks5rchqzgaJpZM4L8U79 .

[BrentWilkins]

Here is the entire sketch minus the copyright and such in the header.

#include <SoftwareSerial.h>

SoftwareSerial Serial7Segment(7, 8); //RX pin, TX pin

int cycles = 0;

void setup() {

  Serial.begin(9600);
  delay(4000);
  Serial.println("OpenSegment Example Code");

  Serial7Segment.begin(9600); //Talk to the Serial7Segment at 9600 bps
  Serial7Segment.write('v'); //Reset the display - this forces the cursor to return to the beginning of the display
}

void loop()
{
  Serial.println("Displaying: -12.3");
  // Writing 4 digits each time. In this case no need to clear display.
  Serial7Segment.print("-123");
  Serial7Segment.write(0x77); // Decimal control command
  Serial7Segment.write(0b00000100); // Turns on tenths decimal
}

The first line includes the file with the software UART implementation. The next line of code creates an instance of the SoftwareSerial class named Serial7Segment that uses pins 7 & 8. If you want to use SPI instead, I recommend looking at our SPI example.