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MTXPlus+ Design Data - Datasheets etc.

 

This page hosts copies of the manufacturer's datasheets and technical manuals the components used in MTXPlus+  

 

Component Datasheets

CPU

Zilog Z84C0020 20MHz
SRAM Samsung KM684000 512k byte
EEPROM Winbond W27C010 128k byte
VDP

The V9958 is an enhanced version of the V9938

Yamaha V9958 Data Sheet

Yamaha V9958 Tech. Manual

Yamaha V9938 Programmers Guide

A good description of the TMS9918 as used in the MTX can also be found here.

GAL Lattice GAL22V10

or

CPLD Altera EPM7128

RS232

Maxim MAX232 (option)
Flash Memory AMD AM29F040B (option)
Microcontroller/Flash Atmel AT89C55WD (option)

 

CPLD (Altera EPM7128) Resources

Altera USB-Blaster Download Cable User Guide

 

The USB Blaster is used for in system programming of the CPLD

Using ModelSim to Simulate Logic Circuits for Altera FPGA Devices

 

Altera Corporation - University Program, September 2010

Evaluating Power for Altera Devices

 

Altera Application Note, AN74 Ver. 3.01 August 1999

LPM Quick Reference Guide, December 1996

 

Altera Library of Parameterised Modules in Quartus II

Quartus II Quick Start Guide

Altera, Three-Step Design Compilation in Quartus II Software, 2007

Operating Requirements for Altera Devices

Altera Data Sheet, A-DS-OPREQ-09.02, Ver. 9.02December 1999

   

 

MSX Documentation

The video board design is based on the use of the Yamaha V9958, used in the MSX2+ and MSX TurboR computers. The MTXPlus+ video board is very close to the design of the Panasonic TurboR FS-A1GT, modified to use a Sony CXA1645P and also expanded to include "analogue" only RGB output circuits.

I relied heavily on the MSX Service Manuals posted on Hans Otten's great MSX site, the most relevant ones are also available for download from here.

   
   
   
   

RGB Encoders

A number of MSX2 machines used a Sony RGB encoder to generate component video from the V9938 RGB signals.

Datasheet for the Sony CXA1145P RGB Encoder used in MSX2+ & TurboR machines having V9958 VDPs. The datasheet is predominantly in Kanji, but the pin-out and typical NTSC and PAL circuits are readable.

An English datasheet for an Erso ES71145, a clone of the CXA1145

Datasheet for a Sony CXA1645P, a later version of the CXA1145P

What appears to be a later datasheet for the CXA1645P, the document number is the same, but the component values used in the SYNC and SC filters are different (reversed), this is the datasheet that I used for the MTXPlus+ video board design.
   
   
   

 

Integrated Circuit pin-outs

CPU

Z84C0020

SRAM

HM628128

EEPROM

W27C512

VDP

V9958

   

 

 

 

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