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boards:ecb:vdu:start [2019/03/01 06:40]
b1ackmai1er [Firmware]
boards:ecb:vdu:start [2020/08/14 02:46] (current)
tastypies [VDU v1]
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 ===== ECB-VDU ===== ===== ECB-VDU =====
  
-The Video Display Unit (VDU) board is a peripheral that allows direct video display generation. The VDU allows the home brew computer a greater degree of autonomy because it eliminates the dependency on serial terminals and/or external PCs. The VDU uses an SY6545 CRTC to generate a monochrome 80 column by 24 line display compatible with commonly available composite monitors.+The Video Display Unit (VDU) board is a peripheral that allows direct video display generation. The VDU allows the home brew computer a greater degree of autonomy because it eliminates the dependency on serial terminals and/or external PCs. The VDU uses an SY6545 CRTC to generate a monochrome 80 column by 24 line display compatible with composite monitors.
  
  
 ===== Features ===== ===== Features =====
  
-  * 80×24 composite video output display format .+  * Composite video output display format. 
 +  * 80x24, 80x25 or 80x30 display format.
   * Reprogrammable for NTSC or PAL video output.   * Reprogrammable for NTSC or PAL video output.
   * Reprogrammable ROM based character set.   * Reprogrammable ROM based character set.
Line 40: Line 41:
 ==== PCB Gerber files ==== ==== PCB Gerber files ====
  
-The following manufacturing files have been regenerated from the {{:boards:ecb:vdu:ecb_vdu.zip|ecb-vdu.zip}}  file set. Boards have been manufactured and are available on the board inventory page. Video output confirmed working as at {{https://www.retrobrewcomputers.org/lib/exe/fetch.php?tok=1d4388&media=https://www.retrobrewcomputers.org/lib/exe/fetch.php?media=boards:ecb:vdu:ecb-vdu-a-10sep2010.jpg?linkonly|24-Feb-2019}}. Other functions untested.+The following manufacturing files have been regenerated from the {{:boards:ecb:vdu:ecb_vdu.zip|ecb-vdu.zip}}  file set and have been confirmed working.
  
 {{:boards:ecb:vdu:ecb-vdu-1a-19sep2010.zip|:boards:ecb:vdu:ecb-vdu-1a-19sep2010.zip}} {{:boards:ecb:vdu:ecb-vdu-1a-19sep2010.zip|:boards:ecb:vdu:ecb-vdu-1a-19sep2010.zip}}
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 __SY6545A__ __SY6545A__
  
-The ECB-VDU incorporates a 6545 CRT controller (CRTC). The 6545 was a popular design and a range of derivatives and enhanced versions of this design were offered by different manufacturers under the 6545 and 6845 designation. For compatibility with this board the CRTC chip must support 'transparent' mode and 2Mhz operation.+The ECB-VDU incorporates a 6545 CRT controller (CRTC). The 6545 was a popular design and a range of derivatives and enhanced versions of this design were offered by different manufacturers under the 6545 and [[https://en.wikipedia.org/wiki/Motorola_6845|6845]] designation. For compatibility with this board the CRTC chip must support 'transparent' mode and 2Mhz operation.
  
 **Tranparent mode **- provides the ability for the processor to access video memory through CRTC registers. The memory on the ECB-VDU board is not directly accessible by any device on the ECB bus. **Tranparent mode **- provides the ability for the processor to access video memory through CRTC registers. The memory on the ECB-VDU board is not directly accessible by any device on the ECB bus.
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   * Motorolla MC6845   * Motorolla MC6845
  
-A range of data sheets are available {{:boards:ecb:vdu:datasheets-6545-6845.zip|here }} for reference.+A range of data sheets are available {{:boards:ecb:vdu:datasheets-6545-6845.zip|here }}  for reference.
  
 __Resistor network arrays:__ __Resistor network arrays:__
Line 99: Line 100:
  
 The VDU board was designed for a 27C128 16Kb EPROM. Only 2Kb of the EPROM is used in normal use. Jumpers P6, P7 and P8 allows different character fonts to be selected if they have been programed. Larger capacity EPROM can be used i.e 27C256-32Kb & 27C512-64Kb but the extra space is effectively wasted. When using a 32Kb or 64Kb the additional address lines are connected to VCC (i.e. pulled high) so the font data needs to be programed to be on the correct address boundary. The easiest way to achieve this is duplicate and append the original EPROM image to the size of the EPROM. Electrically erasable EPROM can also be used i.e Winbond W27E257 (32Kb) has been tested and confirmed working. The VDU board was designed for a 27C128 16Kb EPROM. Only 2Kb of the EPROM is used in normal use. Jumpers P6, P7 and P8 allows different character fonts to be selected if they have been programed. Larger capacity EPROM can be used i.e 27C256-32Kb & 27C512-64Kb but the extra space is effectively wasted. When using a 32Kb or 64Kb the additional address lines are connected to VCC (i.e. pulled high) so the font data needs to be programed to be on the correct address boundary. The easiest way to achieve this is duplicate and append the original EPROM image to the size of the EPROM. Electrically erasable EPROM can also be used i.e Winbond W27E257 (32Kb) has been tested and confirmed working.
 +
  
 ===== Pictures ===== ===== Pictures =====
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-====== Connectors ======+====== Video Output ======
  
-<note>There isn't a RESET select jumper on this board. RESET is configured for LEGACY mode. To run in KONTRON mode the trace from pin 15 IC26 (74LS241) to ECB connector C29 should be cut and pin 15 IC26 should be connected to ECB connector C26</note>+The video output format for the ECB-VDU card is set by the ROMWBW bios initialization. The display format is configured for 80x24 line display using the CCIR System B standard which is commonly referred to as "PAL". Configuration options for "NTSC" format are not available but the "PAL" settings have been reported to work well across all monitors. 
 + 
 +^Format^Frame Rate^Interlace^Field Rate^Lines/Frame^Line Rate| 
 +|PAL|25|2/1|50|625|15625| 
 +|NTSC|30|2/1|60|525|15750| 
 + 
 +P2 - 2 pin header for 75 Ohm video output for connecting to a cinch-style video connector for composite video output (pin 1 is signal, 2 is GND). 
 + 
 +====== Input/output connectors ====== 
 + 
 +<note>There isn't a RESET select jumper on this board. RESET is configured for LEGACY mode. To run in KONTRON mode the trace from pin 15 IC26 (74LS241) to ECB connector C31 should be cut and pin 15 IC26 should be connected to ECB connector C26</note>
  
-  * P2 - 2 pin header for 75 Ohm video output for connecting to a cinch-style video connector for composite video output (pin 1 is signal, 2 is GND). 
   * P3 - Parallel printer.   * P3 - Parallel printer.
   * P4 - PS/2 keyboard.   * P4 - PS/2 keyboard.
   * P5 - PS/2 mouse.   * P5 - PS/2 mouse.
   * K3 - Light pen input.   * K3 - Light pen input.
 +
 +====== Keyboard wiring ======
 +
 +===== Version 1 =====
 +
 +{{https://www.retrobrewcomputers.org/lib/plugins/ckgedit/fckeditor/userfiles/image/boards/ecb/vdu/ecb-vdu-kbd1.png?nolink&800x300}}
 +
 +
 +===== Version 1a / 2 =====
 +
 +{{https://www.retrobrewcomputers.org/lib/plugins/ckgedit/fckeditor/userfiles/image/boards/ecb/vdu/p5-p4-v2.png?nolink&240x180  |P4 and P5 version 2 board}}
 +
 +^PS/2 Plug (MINI-DIN6)^Purpose^VDU KBD P4|
 +|Pin 1|PB0 - KBDAT|Pin 3|
 +|Pin 2|Not Used|-|
 +|Pin 3|GND|Pin 5|
 +|Pin 4|VCC (+5v)|Pin 7|
 +|Pin 5|PB1 - KBCLK|Pin 8|
 +|Pin 6|Not Used|-|
 +
 +\\
 +
  
 ====== Jumpers ====== ====== Jumpers ======
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 Control the font character bank selection by setting address lines A11-A13 high or low. The jumpers are pulled high when not jumpered i.e. no jumpers will result in font 8 being selected. The default* is for font 1 to be selected by jumpering P6, P7 & P8. Control the font character bank selection by setting address lines A11-A13 high or low. The jumpers are pulled high when not jumpered i.e. no jumpers will result in font 8 being selected. The default* is for font 1 to be selected by jumpering P6, P7 & P8.
  
-^P6 (A11)^P7 (A12)^P8 (A13)^ADDRESS^FONT^NAME+^P6 (A11)^P7 (A12)^P8 (A13)^ADDRESS^FONT^FORMAT^DISPLAY^FONT DETAILS
-|ON*|ON*|ON*|0000-07FFh|1|DAN WERNER| +|ON*|ON*|ON*|0000-07FFh|1|10×8|80×24/25|VDU-DW.ROM - DAN WERNER ENGLISH
-|ON|ON|OFF|0800-0FFFh|2| | +|ON|ON|OFF|0800-0FFFh|2|10×8|80×24/25|80Z.ROM - K&P 80 GERMAN
-|ON|OFF|ON|1000-17FFh|3| | +|ON|OFF|ON|1000-17FFh|3|8×8|80×30|8X8_80X30B.ROM - THIN ENGLISH
-|ON|OFF|OFF|1800-1FFFh|4| | +|ON|OFF|OFF|1800-1FFFh|4| | | | 
-|OFF|ON|ON|2000-27FFh|5| | +|OFF|ON|ON|2000-27FFh|5| | | | 
-|OFF|ON|OFF|2800-2FFFh|6| | +|OFF|ON|OFF|2800-2FFFh|6| | | | 
-|OFF|OFF|ON|3000-37FFh|7| | +|OFF|OFF|ON|3000-37FFh|7| | | | 
-|OFF|OFF|OFF|3800-3FFFh|8| |+|OFF|OFF|OFF|3800-3FFFh|8| | | |
  
 __K1 & K2__ __K1 & K2__
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   * K1 - Jumper pins 2-3.   * K1 - Jumper pins 2-3.
   * K2 - Jumper pins 1-2.   * K2 - Jumper pins 1-2.
 +
 +^A (K1)^B (K2)^C (0)^D (1)^QA (P14)^QB (P13)^QC (P12)^QD (P11)^RCO (P15)^Comment|
 +|0|0|0|1|7.2MHz|3.6MHz|1.8MHz|1.4MHz|0.95MHz| |
 +|0|1|0|1|6.9Mhz|4.6Mhz|2.3MHz|1.8MHz|1.22MHz| |
 +|1|0|0|1|8MHz|4MHz|2MHz|1.6MHz|1.07MHz|Default|
 +|1|1|0|1|8MHz|5.4MHz|2.7MHz|2.2MHz|1.43MHz| |
  
 \\ \\
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 ====== Firmware ====== ====== Firmware ======
  
-The ECB-VDU requires the EPROM to be programed with font data.+The ECB-VDU requires the EPROM to be programed with font data. A font is 2Kb in size and contains the bit mapped images for 128 unique characters and as the 27C128 font EPROM is 16Kb in size, it can be programed with up to 8 fonts. Font selection can only be changed by setting the address jumpers P6, P7, P8. The ECB-VDU does not support font changes through software or programmable bit mapped graphics. The ECB-VDU cannot display 256 unique characters because it uses bit 7 of each character as an attribute bit. Any character with the attribute set will display as per the cursor mode i.e reversed, slow flash, fast flash.
  
-Dan Warner has provided an English font file: {{:boards:ecb:vdu:archive:vdu-dw.zip|:boards:ecb:vdu:archive:vdu-dw.zip}} +Different font firmware can be found on the [[:boards:ecb:vdu:fonts|]] page.
- +
-Font files can be edited and developed using the font editor utility: +
- +
-{{:boards:ecb:vdu:archive:vdu_font_edit.zip|:boards:ecb:vdu:archive:vdu_font_edit.zip}} +
- +
-The original German orientated K&P 80 font file is available [[:boards:ecb:vdu:kp80interface|here]] and there are many bit mapped fonts freely available on the internet. +
- +
-Each font is 2Kb in size and contains the bit mapped images for 256 unique characters. Each font character is a 10x8 bit matrix i.e. 8 bytes with 16 bytes reserved for each character (8 bytes are unused and not displayed). The 27C128 font EPROM is 16Kb in size, so it can be programed with up to 8 fonts. Font selection can only be changed by setting the address jumpers P6, P7, P8. The ECB-VDU does not support font changes through software or programmable bit mapped graphics.+
  
  
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 <code> <code>
 VDUENABLE    .SET    TRUE        ; TRUE FOR VDU BOARD VIDEO & KBD SUPPORT VDUENABLE    .SET    TRUE        ; TRUE FOR VDU BOARD VIDEO & KBD SUPPORT
 +</code>
 +
 +The default screen format is 80x24 but a few other formats are possible i.e. 80x30:
 +
 +<code>
 +VDUSIZ        .EQU    V80X30        ; VDU DISPLAY FORMAT V80X24, V80X25, V80X30
 </code> </code>
  
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 <code> <code>
 B>STAT LST:=CRT: B>STAT LST:=CRT:
 +or
 +B>PIP LST:=STORY.TXT
 </code> </code>
  
boards/ecb/vdu/start.1551440402.txt.gz · Last modified: 2019/03/01 06:40 by b1ackmai1er
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