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boards:ecb:vdu:start [2019/01/14 02:18]
b1ackmai1er [Parts]
boards:ecb:vdu:start [2019/04/03 09:18] (current)
b1ackmai1er [Jumpers]
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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 25 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 =====
  
-  * 80×25 NTSC composite ​video output display format . +  * Composite ​video output ​display format. 
-  * Reprogrammable for PAL video output.+  * 80x24, 80x25 or 80x30 display format. 
 +  * Reprogrammable for NTSC or PAL video output.
   * Reprogrammable ROM based character set.   * Reprogrammable ROM based character set.
   * PS/2 keyboard interface.   * PS/2 keyboard interface.
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-===== Hardware Documentation ​=====+===== Acknowledgement ​=====
  
-The following files describe ​the V2 board. Kicad and Gerber files are unavailable ​for this version. Differences between this version and previous versions are described as changes to headers and new pcb routing.+ECB-VDU was [[:​boards:​ecb:​vdu:​development|developed by Andrew Lynch]] based on the [[:​boards:​ecb:​vdu:​kp80interface|K&​P 80 Column Interface]] ​for the Sharp MZ-700.
  
  
-==== Schematics ​====+===== Hardware Documentation =====
  
-{{:​boards:​ecb:​vdu:​printing_vdu_v2-sch.pdf|:​boards:​ecb:​vdu:​printing_vdu_v2-sch.pdf}}+Additional useful information regarding the ECB-VDU can be found in {{:​boards:​ecb:​vdu:​archive:​my_understanding_of_the_n8vem_vdu_board.doc|My Understanding of the N8VEM VDU}}  ​board ​ by Oscar Vermeulen.
  
-==== Board Layout ====+__Versions__
  
-{{:​boards:​ecb:​vdu:​printing_vdu_v2-brd.pdf|:​boards:​ecb:​vdu:​printing_vdu_v2-brd.pdf}}+Three {{https://​www.retrobrewcomputers.org/​lib/​exe/​fetch.php?​media=boards:​ecb:​vdu:​ecb_vdu_versions.png?​linkonly|versions}} of the ECB-VDU design exist:
  
-====== Gerber Files ======+  * Version 1 "​Full"​ (original version) 
 +  * Version 1 "​A"​ 
 +  * Version 2
  
-Version: ECB-VDU-10-Sep-2010+Kicad and Gerber manufacturing files have been lost for version 2, although schematics and board files are available in pdf form below. The following files describe the Version ​1 "A" board for which Kicad board files are available. Manufacturing Gerber files have been generated for this version. Differences between version 1 "​A"​ and version 2 are described as changes to headers and new pcb routing. i.e no loss of functionality.
  
-==== PCB Gerber files ====+__Version 1 "​A"​ : ECB-VDU-1A-19Sep2010__
  
-The following manufacturing files have been regenerated from the ecb-vdu.zip file set shown below and have not been tested. Boards being manufactured as at 26 December 2018. 
  
-{{:​boards:​ecb:​vdu:​ecb-vdu-a-10sep2010.zip|:​boards:​ecb:​vdu:​ecb-vdu-a-10sep2010.zip}}+==== PCB Gerber files ====
  
-{{:​boards:​ecb:​vdu:​ecb_vdu.zip|:boards:ecb:vdu:ecb_vdu.zip}}+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.
  
-===== Hardware Documentation ===== +{{:​boards:​ecb:​vdu:​ecb-vdu-1a-19sep2010.zip|:​boards:​ecb:​vdu:​ecb-vdu-1a-19sep2010.zip}}
- +
-The following files describe the V2 boardKicad and Gerber files are unavailable for this version. Differences between this version and previous versions are described as changes to headers and new pcb routing.+
  
  
 ==== Schematics ==== ==== Schematics ====
 +
 +{{:​boards:​ecb:​vdu:​printing_vdu_v1-sch.pdf|:​boards:​ecb:​vdu:​printing_vdu_v1-sch.pdf}}
  
 {{:​boards:​ecb:​vdu:​printing_vdu_v2-sch.pdf|:​boards:​ecb:​vdu:​printing_vdu_v2-sch.pdf}} {{:​boards:​ecb:​vdu:​printing_vdu_v2-sch.pdf|:​boards:​ecb:​vdu:​printing_vdu_v2-sch.pdf}}
 +
  
 ==== Board Layout ==== ==== Board Layout ====
 +
 +{{:​boards:​ecb:​vdu:​printing_vdu_v1-brd-full.pdf|:​boards:​ecb:​vdu:​printing_vdu_v1-brd-full.pdf}}
  
 {{:​boards:​ecb:​vdu:​printing_vdu_v2-brd.pdf|:​boards:​ecb:​vdu:​printing_vdu_v2-brd.pdf}} {{:​boards:​ecb:​vdu:​printing_vdu_v2-brd.pdf|:​boards:​ecb:​vdu:​printing_vdu_v2-brd.pdf}}
  
-====== Gerber Files ====== +Notethat the ECB-VDU ​does not support KONTRON reset modeUsing this board requires all [[:​boards:​ecb:​ecbbusinfo#​ecb_connector_requirements|other boards]] to be set to Legacy mode or the board needs to be patched to the KONTRON configuration.
- +
-Version: ECB-VDU-A 10-Sep-2010 +
- +
-==== PCB Gerber files ==== +
- +
-The following manufacturing files have been regenerated from the ecb-vdu.zip file set shown below and have not been testedBoards being manufactured as at 26 December 2018. +
- +
-{{:​boards:​ecb:​vdu:​ecb-vdu-a-10sep2010.zip|:boards:​ecb:​vdu:​ecb-vdu-a-10sep2010.zip}}+
  
-{{:​boards:​ecb:​vdu:​ecb_vdu.zip|:​boards:​ecb:​vdu:​ecb_vdu.zip}} 
  
 ==== Parts ==== ==== Parts ====
  
 {{:​boards:​ecb:​vdu:​vdu-parts.txt|:​boards:​ecb:​vdu:​vdu-parts.txt}} {{:​boards:​ecb:​vdu:​vdu-parts.txt|:​boards:​ecb:​vdu:​vdu-parts.txt}}
 +
  
 ==== Parts substitution:​ ==== ==== Parts substitution:​ ====
Line 73: Line 71:
 __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.
Line 93: Line 91:
   * 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:__
  
-The 1K5 resistor networks are specified as 10 pin units. These are difficult to obtain and 9 pin units can be substituted as the the last resistor is not used. Additionally the value for these pull up resistors ​ are not critical and anything in the range 1K5 to 4K7 should work.+The 1K5 resistor networks are specified as 10 pin units. These are difficult to obtain and 9 pin units can be substituted as the the last resistor is not used. Additionally the value for these pull up resistors are not critical and anything in the range 1K5 to 4K7 should work.
  
-__Other:__+__EPROM:__
  
-__Capacitor__+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.
  
-__Transistor __ 
  
 +===== Pictures =====
  
-====== Pictures ======+Version 1A board: 
 + 
 +{{https://​www.retrobrewcomputers.org/​lib/​plugins/​ckgedit/​fckeditor/​userfiles/​image/​boards/​ecb/​vdu/​ecb_vdu_1a-19sep2010.jpg?​nolink&​800x465}} 
 + 
 +Version 1 board:
  
 [[https://​www.retrobrewcomputers.org/​lib/​exe/​fetch.php?​tok=79721d&​media=https://​www.retrobrewcomputers.org/​lib/​plugins/​ckgedit/​fckeditor/​userfiles/​image/​boards/​ecb/​vdu/​ecb-vdu.jpg|{{https://​www.retrobrewcomputers.org/​lib/​plugins/​ckgedit/​fckeditor/​userfiles/​image/​boards/​ecb/​vdu/​ecb-vdu.jpg?​direct&​800x463|www.retrobrewcomputers.org_lib_plugins_ckgedit_fckeditor_userfiles_image_boards_ecb_vdu_ecb-vdu.jpg}}]] [[https://​www.retrobrewcomputers.org/​lib/​exe/​fetch.php?​tok=79721d&​media=https://​www.retrobrewcomputers.org/​lib/​plugins/​ckgedit/​fckeditor/​userfiles/​image/​boards/​ecb/​vdu/​ecb-vdu.jpg|{{https://​www.retrobrewcomputers.org/​lib/​plugins/​ckgedit/​fckeditor/​userfiles/​image/​boards/​ecb/​vdu/​ecb-vdu.jpg?​direct&​800x463|www.retrobrewcomputers.org_lib_plugins_ckgedit_fckeditor_userfiles_image_boards_ecb_vdu_ecb-vdu.jpg}}]]
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 [[:​boards:​ecb:​vdu:​gallery|Gallery]] [[:​boards:​ecb:​vdu:​gallery|Gallery]]
  
-====== 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 ​C29 should be cut and pin 15 IC26 should be connected to ECB connector C26</​note>​+====== Video Output ====== 
 + 
 +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 ======
 +
 +{{https://​www.retrobrewcomputers.org/​lib/​plugins/​ckgedit/​fckeditor/​userfiles/​image/​boards/​ecb/​vdu/​ecb-vdu-kbd1.png?​nolink&​800x300}}
  
  
 ====== Jumpers ====== ====== Jumpers ======
  
-  ​* P6, P7P8 - Character Bank selection. +__P6, P7 & P8__ 
-  * K1 - Character set A. Default: ​Jumper pins 2-3. + 
-  * K2 - Character set B. Default: ​Jumper pins 1-2.+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 defaultis for font 1 to be selected by jumpering ​P6, P7 P8
 + 
 +^P6 (A11)^P7 (A12)^P8 (A13)^ADDRESS^FONT^FORMAT^DISPLAY^FONT DETAILS| 
 +|ON*|ON*|ON*|0000-07FFh|1|10×8|80×24/​25|VDU-DW.ROM - DAN WERNER ENGLISH| 
 +|ON|ON|OFF|0800-0FFFh|2|10×8|80×24/​25|80Z.ROM - K&P 80 GERMAN| 
 +|ON|OFF|ON|1000-17FFh|3|8×8|80×30|8X8_80X30B.ROM - THIN ENGLISH| 
 +|ON|OFF|OFF|1800-1FFFh|4| | | | 
 +|OFF|ON|ON|2000-27FFh|5| | | | 
 +|OFF|ON|OFF|2800-2FFFh|6| | | | 
 +|OFF|OFF|ON|3000-37FFh|7| | | | 
 +|OFF|OFF|OFF|3800-3FFFh|8| | | | 
 + 
 +__K1 & K2__ 
 + 
 +Provide ​selection ​for the dot clock rate based on the crystal frequencyThe default setting provides a 2Mhz dot clock from a 16Mhz crystal i.e divide by 8. Other options have not been documented. 
 + 
 +Defaults: 
 + 
 +  * K1 - Jumper pins 2-3. 
 +  * K2 - Jumper pins 1-2. 
 + 
 +^A (K1)^(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| | 
 + 
 +\\ 
 + 
 + 
 +====== Ports ====== 
 + 
 +The ECB-VDU has an fixed port address F0-F7h. 
 + 
 +^ADDRESS^DEVICE^PURPOSE| 
 +|F0h|6545 VDU|READ VDU| 
 +|F1h|6545 VDU|WRITE VDU| 
 +|F2h|6545 VDU|VDU STATUS/​REGISTER| 
 +|F3h|6545 VDU|VDU DATA REGISTER| 
 +|F4h|8255 PPI|PPI PORT A| 
 +|F5h|8255 PPI|PPI PORT B| 
 +|F6h|8255 PPI|PPI PORT C| 
 +|F7h|8255 PPI|PPI CONTROL PORT| 
 + 
 +\\ 
 + 
 + 
 +====== Firmware ====== 
 + 
 +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. 
 + 
 +Different font firmware can be found on the [[:boards:​ecb:​vdu:​fonts|]] page. 
 + 
 + 
 +===== Software ===== 
 + 
 +ROMWBW supports the ECB-VDU but does not have the required support included in the default build. A custom build is required to enable the VDU to be setup as the CP/M CRT: device. The following configuration change is required: 
 + 
 +SBC_std_cust.asm 
 + 
 +<​code>​ 
 +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>​ 
 + 
 +Output to the CRT: device can be tested using the CP/M PIP command (Use Ctrl-Z to stop): 
 + 
 +<​code>​ 
 +B>PIP CRT:=CON: 
 +</​code>​ 
 + 
 +Input and output can be redirected to the VDU CRT: device with the CP/M STAT command (Revert using STAT CRT:​=TTY:​):​ 
 + 
 +<​code>​ 
 +B>STAT CON:=CRT: 
 +</​code>​ 
 + 
 +With CP/M's redirection capability, the CRT: device can also be used as the LST: "​printer"​ device. 
 + 
 +<​code>​ 
 +B>STAT LST:=CRT: 
 +or 
 +B>PIP LST:​=STORY.TXT 
 +</​code>​ 
 + 
 +Using Ctrl-P will also direct anything output to the terminal the CRT: (VDU). 
 + 
 +Additionally,​ to configure the VDU as primary input and output under CP/M, use the following configuration option: 
 + 
 +<​code>​ 
 +CRTACT ​       .SET    TRUE        ; TRUE TO ACTIVATE CRT AT STARTUP (BOOT ON CRT) 
 +</​code>​ 
 + 
 +ROMWBW also supports activating the CRT: as the primary console at boot-up using JP2 on the SBC V2 (the 1-bit I/O port). 
 + 
 +The printer port P3, Mouse port P5 and Light Pen input are currently not supported by ROMWBW. 
 + 
 +Programming examples including terminal and test programs can be found on the [[:​boards:​ecb:​vdu:​software|]] page. 
  
 ====== Resources ====== ====== Resources ======
boards/ecb/vdu/start.1547450314.txt.gz · Last modified: 2019/01/14 02:18 by b1ackmai1er
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