Upload fonts to external SPI Flash¶

The Commercial edition allows to use the external 8 Mbits = 1 MBytes x 8 SPI Flash memory, labelled U1 on the EXT3 and EXT3.1 extension boards, to store fonts.

The standard reference of the SPI Flash memory is MX25V2006 .

The corresponding chip select pin is numbered 8 on the EXT3 and EXT3.1 extension boards.

Variable	Number	Signal	Type	Function
`.flashCS`	8	Flash /CS	`I`	Flash chip select

Option 1: Segger J-Flash SPI¶

The Segger J-Link programmer-debugger offers a fast way to upload the fonts to the external SPI Flash of the EXT3. The List of supported SPI flash devices includes the MX25V2006.

Configure¶

Connect from the J-Link programmer-debugger to the extension board: the SPI signals CLK, /CS, DI or MOSI, DO or MISO; and power lines VTref and GROUND.

J-Link Channel	J-Link Pin	Extension board Pin	Signal
`VTref`	`1`	1	VCC +3.3V from external supply
`CLK`	`9`	2	SPI SCK
`DO` or `MISO`	`13`	6	SPI MISO
`DI` or `MOSI`	`5`	7	SPI MOSI
`nCS`	`7`	8	Flash /CS
`GROUND`	`4`, `6`, `8`, `10` or `12`	10	Ground

To power the extension board, either provide an external 3.3V; or connect a 3.3V regulator to the J-Link programmer-debugger 5V-Supply output and turn power on.

J-Link Channel	J-Link Pin	Extension board Pin	Signal
`5V-Supply`	`19`	-	VCC +5V supplied by J-Link

For more information,

Please refer to https://www.segger.com/products/debug-probes/j-link/tools/j-flash-spi/ .

Use¶

Two options: by command line or GUI.

Command lineGUI

Launch

$
JFlashSPI_CL -open Fonts_511.hex -auto

JFlashSPI_CL loads the Fonts_511.hex file, connects to the SPI Flash, uploads and verifies, then disconnects.

Launch the JFlashSPIExe application.

Call the menu File > Open data file… and select the Fonts_511.hex file; or drag-and-drop the Fonts_511.hex file onto the application.

Call the menu Target > Connect to identify the external SPI Flash automatically and then the menu Target > Program to upload and flash the external SPI Flash automatically.

Call the menu File > Exit to quit the application.

More information is available at the page J-Flash SPI — Direct programming of (Q)SPI flashes on the Segger website.

Option 2: highView Fonts Manager¶

Configure¶

Ensure the targeted MCU provides enough memory in Flash to store the fonts.

Open the hV_Fonts_Manager.ino project.

Set the options to write sector 0 and the fonts, and generate the header file with the fonts enumeration.

Optionally, set the options to read sector 0 and the fonts.

#define WRITE_FLASH_SECTOR_0 1 ///< Write or update sector 0
#define WRITE_FLASH_FONTS 1 ///< Write fonts to Flash

#define SIMULATE_FLASH_SECTOR_0 0 ///< Simulate sector 0

#define READ_FLASH_SECTOR_0 1 ///< Read sector 0
#define READ_FLASH_FONTS 1 ///< Read fonts from Flash

#define GENERATE_FONTS_ENUMERATION 1 ///< Generate code of header file with fonts enumeration

Use¶

Select the fonts to include under the setup() function.

loadFont(Font_DejaVuMono12);
loadFont(Font_DejaVuMono12b);

Build and link, upload and run.

Copy the generated fonts enumeration into the hV_Font_Flash header file for later use with the Fonts from external SPI Flash option.