Wim Huiskamp
Library for Princeton PT6301 VFD controller. Used in Futaba CIG VFD tubes.
This is a library for the Princeton PT6301 VFD controller. The controller is used by Futaba 'Chip In Glass' (CIG) VFD tubes. The device supports upto 20 Grids of 5x7 matrix segments for 2 rows of characters (A and B). It also supports 1 additional segment for 2 rows (A and B). In addition to the internal ROM character set, the PT6301 also supports 16 User Defined Characters.
The PT6301 has an SPI Serial interface. Control data consists of an 8-bit command and one or more data bytes. Command and data are sent LSB first and latched on rising edge of CLK. Idle CLK is high. Data address is auto incremented. Same for Icon and UDC addresses. The commands and data are transmitted during CE low and latched on rising CE edge.
The PT6301 has internal memory for all characters and icons. The content is automatically displayed on the tube. The memory consists of two banks (row A and row B) for character memory and two banks (row A and row B) for icon memory. Each of those banks is accessed by separate commands. However, these command do not support addressing individual locations in the memory. Memory updates always start at address 0 in the selected row A or B. Consequently, the whole displaymemory needs to be rewritten when any location (except for 0) is to be updated. The library therefor uses a local mirror memory to store the display content, update one or more characters in the mirror-memory as needed, and rewrite the whole display memory from the mirror-content. The write-back is performed by calling the 'refresh' method. Additional advantage of the mirror-memory is that we can also implement wrap-around and scrolling from row A to B for multi-line displays.
The lib was tested on displays salvaged from two Samsung cable TV receivers (e.g. Samsung SMT-C7140 and Samsung SMT-G7400). The examples don't use all features as this depends on how the controller has been applied inside the tube. The SMT-C7140 for example does not use the icon segments, but uses a separate grid to display a User Defined Character. The segments in the UDC light up specific icons (eg mail, clock). See picture below.
The example code is
I stumbled on the SMT-C7140 display and found some useful reverse engineering info by Codebeat here that helped to identify the controller. The pinout for the VFD tube connector (starting from the left side in the picture above) is: GND1, GND2, +35V DC (switched), 5V DC supply (switched), OSC pin (RC network between 5V and GND), /RST, /CS, CLK, DAT, NC, NC
The 35V DC is generated on the PCB by a DC/DC converter. The 35V generator, the 5V supply and the filament supply are all enabled by a pin on the connector at the bottom of the PCB.
The SMT-G7400 had a similar schematic for the tube connection as the SMT-C7140, but used a dedicated processor on the display PCB. The processor was removed and replaced by flying wires to an mbed LPC1768 for testing with the lib.
General explanation of VFD is here
Diff: PT6302.h
- Revision:
- 1:aa0195b0f83c
- Parent:
- 0:ecc29c13a997
--- a/PT6302.h Sun Dec 03 18:02:15 2017 +0000
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,461 +0,0 @@
-/* mbed PT6302 Library, for Princeton PT6302 VFD controller
- * Note the PT6302 is identical to the OKI ML9208
- *
- * Copyright (c) 2017, v01: WH, Initial version
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in
- * all copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
- * THE SOFTWARE.
- */
-
-#ifndef PT6302_H
-#define PT6302_H
-
-// Select one of the testboards for Princeton PT6302 VFD controller
-#include "PT6302_Config.h"
-#include "PT6302_UDC.h"
-
-/** An interface for driving Princeton PT6302 VFD controller
- *
- * @code
- *
- * #if (PT6302_TEST == 1)
- * // Direct driving of PT6302 Test
- *
- * #include "mbed.h"
- * #include "PT6302.h"
- *
- * DigitalOut myled(LED1);
- * Serial pc(USBTX, USBRX);
- *
- * // PT6302 declaration, Default setting 16 Grids @ 35 Segments
- * PT6302 PT6302(p5, p7, p8); // DI, CLK, CS
- *
- * int main() {
- * pc.printf("Hello World: PT6302 test\n\r");
- *
- * PT6302.cls();
- *
- * PT6302.writeData((char)'H', 9);
- * PT6302.writeData((char)'e', 8);
- * PT6302.writeData((char)'l', 7);
- * PT6302.writeData((char)'l', 6);
- * PT6302.writeData((char)'o', 5);
- * wait(2);
- * PT6302.setBrightness(PT6302_BRT0);
- * wait(2);
- * PT6302.setBrightness(PT6302_BRT3);
- *
- * while(1) {
- * myled = !myled;
- * wait(1);
- * }
- * }
- * #endif
- *
- * @endcode
- */
-
-
-//PT6302 Display and Annunciator data
-#define PT6302_MAX_NR_GRIDS 16
-#define PT6302_BYTES_PER_GRID 1
-
-//Memory size in bytes for Display and Annunciators
-#define PT6302_DSP_MEM 16
-#define PT6302_ADD_MEM 16
-//#define PT6302_UDC_MEM 8
-
-//SPI Serial control data consists of an 8-bit command and one or more data bytes.
-//Command and data are sent LSB first and latched on rising edge of CLK. Idle CLK is high.
-//Data address is auto incremented.
-//The commands and data are transmitted during CE low and latched on rising CE edge.
-//Multiple PT6302 devices on the same bus can only be distinguised by the CE control.
-
-//Command delay
-#define PT6302_CMD_DLY 8
-#define PT6302_CS_DLY 16
-
-//
-//Set Char data command (DCRAM)
-// 0 0 0 1 DA3 DA2 DA1 DA0
-#define PT6302_DATA_REG 0x10
-
-//DA3..DA0 DCRAM Address
-#define PT6302_DADR_MSK 0x0F
-
-//Char data (2nd byte, 3rd byte ...)
-//DA7..DA0 Character Data
-#define PT6302_DATA_MSK 0xFF
-
-
-//
-//Set UDC data command (CGRAM)
-// 0 0 1 0 * UA2 UA1 UA0
-#define PT6302_UDC_REG 0x20
-
-//UA2..UA0 CGRAM Address (UDC RAM address)
-#define PT6302_UADR_MSK 0x07
-#define PT6302_NR_UDC 8
-
-//User Defined Characters (UDCs) consist of 5x7 dots and are defined by a 5 byte bitpattern.
-//UDC data (2nd byte .. 6th byte)
-// D7 D6 D5 D4.. D1 D0
-// 0 * CD30 CD25 ...... CD0
-// 1 * CD31 CD26 ...... CD1
-// 2 * CD32 CD27 ...... CD2
-// 3 * CD33 CD28 ...... CD3
-// 4 * CD34 CD29 ...... CD4
-//
-#define PT6302_UDC_MSK 0x7F
-
-//CD34..CD0 UDC Data
-//UDC is a 5x7 Matrix pattern that will show on the VFD as
-// 0 C0 C1 C2 C3 C4
-// 1 C5 C6 ..... C9
-// . .............
-// . .............
-// . .............
-// 6 C30 C31 ... C34
-//
-
-//UDCs are defined by a 5x7 matrix and stored as 5 bytes
-typedef char UDCData_t[5];
-
-
-//
-//Set Additional data command (ADRAM), Used for annunciators etc
-// 0 0 1 1 AA3 AA2 AA1 AA0
-#define PT6302_ADAT_REG 0x30
-
-//AA3..AA0 ADRAM Address (Additional data)
-#define PT6302_AADR_MSK 0x0F
-
-//* * * * * * AD1 AD0 Additional Data (2nd byte, 3rd byte, ..)
-#define PT6302_ADAT_MSK 0x03
-
-
-//
-//Set Port data command (General output)
-// 0 1 0 0 * * P1 P0
-#define PT6302_PDAT_REG 0x40
-
-//P1 P0 Port data
-#define PT6302_PDAT_MSK 0x03
-
-
-
-//
-//Set Brightness command
-// 0 1 0 1 * DC2 DC1 DC0
-#define PT6302_BRT_REG 0x50
-#define PT6302_BRT_MSK 0x07
-
-//DC2..DC0 Brightness Level (0..7)
-//Note Brightness relationship between the number of active Grids (period) and the BRT value (duty cycle)
-#define PT6302_BRT_0 0x00 //Duty 8/16 (Default)
-#define PT6302_BRT_1 0x01
-#define PT6302_BRT_2 0x02
-#define PT6302_BRT_3 0x03
-#define PT6302_BRT_4 0x04
-#define PT6302_BRT_5 0x05
-#define PT6302_BRT_6 0x06
-#define PT6302_BRT_7 0x07 //Duty 15/16
-
-#define PT6302_BRT_DEF (PT6302_BRT_2)
-
-
-//
-//Grid control command
-// 0 1 1 0 * GN2 GN1 GN0
-#define PT6302_GRID_REG 0x60
-#define PT6302_GRID_MSK 0x07
-
-//Grids
-//
-// GN2 GN1 GN0
-// 0 0 0 G1 to G16 // Default
-// 0 0 1 G1 to G9
-// 0 1 0 G1 to G10
-// 0 1 1 G1 to G11
-// 1 0 0 G1 to G12
-// 1 0 1 G1 to G13
-// 1 1 0 G1 to G14
-// 1 1 1 G1 to G15
-#define PT6302_GR1_GR9 0x01
-#define PT6302_GR1_GR10 0x02
-#define PT6302_GR1_GR11 0x03
-#define PT6302_GR1_GR12 0x04
-#define PT6302_GR1_GR13 0x05
-#define PT6302_GR1_GR14 0x06
-#define PT6302_GR1_GR15 0x07
-#define PT6302_GR1_GR16 0x00
-
-
-//
-//Display On/Off command
-// 0 1 1 1 * * H L
-#define PT6302_DSPL_REG 0x70
-#define PT6302_DSPL_MSK 0x03
-
-//Display Mode
-// H L Display operating state
-// 0 0 Normal (default)
-// 0 1 Off
-// 1 0 All Segments and Additional Segments On
-// 1 1 All Segments and Additional Segments On
-#define PT6302_DSPL_NRM 0x00
-#define PT6302_DSPL_OFF 0x01
-#define PT6302_DSPL_ON 0x02
-
-
-/** A class for driving Princeton PT6302 VFD controller
- *
- * @brief Supports upto 16 Grids of 35 matrix segments.
- * Also supports 2 additional segments and 2 port pins.
- * SPI bus interface device.
- */
-class PT6302 {
- public:
-
- /** Enums for display mode */
- enum Mode {
- Grid9_Add2 = PT6302_GR1_GR9,
- Grid10_Add2 = PT6302_GR1_GR10,
- Grid11_Add2 = PT6302_GR1_GR11,
- Grid12_Add2 = PT6302_GR1_GR12,
- Grid13_Add2 = PT6302_GR1_GR13,
- Grid14_Add2 = PT6302_GR1_GR14,
- Grid15_Add2 = PT6302_GR1_GR15,
- Grid16_Add2 = PT6302_GR1_GR16
- };
-
- /** Datatypes for display data */
-// typedef char DisplayData_t[PT6302_DISPLAY_MEM];
-// typedef char DisplayAdd_t[PT6302_ADD_MEM];
-
- /** Constructor for class for driving Princeton PT6302 VFD controller
- *
- * @brief Supports upto 16 Grids of 35 matrix segments.
- * Also supports 2 additional segments and 2 port pins.
- * SPI bus interface device.
- * @param PinName mosi, sclk, cs SPI bus pins
- * @param Mode selects number of Grids and Segments (default 16 Grids, 2 additional segments)
- */
- PT6302(PinName mosi, PinName sclk, PinName cs, Mode mode = Grid16_Add2);
-
- /** Clear the screen
- *
- * @param none
- * @return none
- */
- void cls();
-
- /** Set Brightness
- *
- * @param char brightness (3 significant bits, valid range 0..7 (dutycycle linked to number of grids)
- * @return none
- */
- void setBrightness(char brightness = PT6302_BRT_DEF);
-
- /** Set the Display mode On/off
- *
- * @param bool display mode
- * @return none
- */
- void setDisplay(bool on);
-
-
- /** Set Port
- *
- * @param char port (2 least significant bits)
- * @return none
- */
- void setPort (char port = 0);
-
- /** Set User Defined Characters (UDC)
- *
- * @param unsigned char udc_idx The Index of the UDC (0..7)
- * @param UDCData_t udc_data The bitpattern for the UDC (5 bytes)
- * @return none
- */
- void setUDC(unsigned char udc_idx, UDCData_t udc_data);
-
-
- /** Write Data to PT6302
- *
- * @param char data Character code
- * @param char address Parameter for data
- * @return none
- */
- void writeData(char data, char address);
-
- /** Write Additional Data to PT6302
- *
- * @param char adata Additional code (annunciator)
- * @param char address Parameter for data
- * @return none
- */
- void writeAData(char adata, char address);
-
- protected:
- /** Write command and parameters to PT6302
- *
- * @param char cmd Command byte
- * @param char data Parameter for command
- * @return none
- */
- void _writeCmd(char cmd, char data);
-
- /** Write command to PT6302
- *
- * @param char cmd Command byte
- * @return none
- */
- void _writeCmd(char cmd);
-
- char _port;
-
- private:
- SPI _spi;
- DigitalOut _cs;
- Mode _mode;
-
- /** Init the SPI interface and the controller
- *
- * @param none
- * @return none
- */
- void _init();
-
- /** Helper to reverse all command or databits. The PT6302 expects LSB first, whereas SPI is MSB first
- *
- * @param char data
- * @return bitreversed data
- */
- char _flip(char data);
-
-};
-
-
-#if (HANNSTAR_TEST == 1)
-// Derived class for HANNSTAR display unit
-// Grids 1-16 all display 35 segment matrix characters and no Additional segments.
-//
-
-//HANNSTAR Display data
-#define HANNSTAR_NR_GRIDS 16
-#define HANNSTAR_NR_DIGITS 16
-//#define HANNSTAR_NR_UDC 8
-
-//HANNSTAR Memory size in bytes for Display
-//#define HANNSTAR_DISPLAY_MEM (HANNSTAR_NR_GRIDS * PT6302_BYTES_PER_GRID)
-
-
-//
-//Set Port data command (General output)
-// 0 1 0 0 * * P1 P0
-
-//P0 P1 Port data, P0 is used for VGen control
-#define PT6302_HANN_PDAT_MSK 0x02
-
-//P0 is used to control the VFD Voltage generator (-24V and Filament)
-#define PT6302_HANN_VGEN 0x01
-
-
-
-/** Constructor for class for driving Princeton PT6302 VFD controller as used in HANNSTAR
- *
- * @brief Supports 16 Grids of 35 Segments without additional Segments.
- *
- * @param PinName mosi, sclk, cs SPI bus pins
- */
-class PT6302_HANNSTAR : public PT6302, public Stream {
- public:
-
-/** Constructor for class for driving Princeton PT6302 VFD controller as used in HANNSTAR
- *
- * @brief Supports 16 Grids of 35 Segments without additional Segments.
- *
- * @param PinName mosi, sclk, cs SPI bus pins
- */
- PT6302_HANNSTAR(PinName mosi, PinName sclk, PinName cs);
-
-#if DOXYGEN_ONLY
- /** Write a character to the Display
- *
- * @param c The character to write to the display
- * @return char written
- */
- int putc(int c);
-
- /** Write a formatted string to the Display
- *
- * @param format A printf-style format string, followed by the
- * variables to use in formatting the string.
- */
- int printf(const char* format, ...);
-#endif
-
- /** Locate cursor to a screen column
- *
- * @param column The horizontal position from the left, indexed from 0
- * @return none
- */
- void locate(int column);
-
- /** Clear the screen and locate to 0
- *
- * @param bool clrAll Clear Icons also (default = false)
- */
- void cls(bool clrAll = false);
-
- /** Number of screen columns
- *
- * @param none
- * @return columns
- */
- int columns();
-
- /** Set Port
- *
- * @param char port (Only Bit 1 is used)
- * @return none
- */
- void setPort (char port = 0);
-
- /** Set VFD VGen
- *
- * @param bool on
- * @return none
- */
- void setVGen (bool on = true);
-
-protected:
- // Stream implementation functions
- virtual int _putc(int value);
- virtual int _getc();
-
-private:
- int _column; // Current cursor location
- int _columns; // Max number of columns
-
-// DisplayData_t _displaybuffer; // Local mirror for all chars and icons
-};
-#endif
-
-#endif
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