Search found 488 matches

by FARID
Wed Sep 06, 2017 2:03 am
Forum: NES Hardware and Flash Equipment
Topic: EPROM LPT Programmer?
Replies: 33
Views: 10170

Re: LPT EPROM Reader?

I made some modification to the schematic : VCC is only 5v USB (no 6.5v at all) Using a 47uF on VCC line made the read process more stable VPP 13v is generated by using MC34063 Instead of 33K pull down resistors I used 10K pull up resistors (same as Willem Programmer ) But unfortunately Writing EPRO...
by FARID
Sun Sep 03, 2017 7:55 am
Forum: NES Hardware and Flash Equipment
Topic: EPROM LPT Programmer?
Replies: 33
Views: 10170

Re: LPT EPROM Reader?

So I decided to use MC34063 to boost 5v to 12.75v, because it is inexpensive and small. I checked it's datasheet and in page 13 there is an example circuit for 12v --> 28v but I want 5v --> 12.75v so I have to recalculate the parts value. In page 14 there are some great and awesome formula for calcu...
by FARID
Sat Sep 02, 2017 12:48 pm
Forum: NES Hardware and Flash Equipment
Topic: EPROM LPT Programmer?
Replies: 33
Views: 10170

Re: LPT EPROM Reader?

Reading EPROM works fine on windows xp.
Reading a AT27C080 takes 40 seconds.
To be able to access LPT port under windows xp I had to use inpout32.dll
I use MS visual C++ v6.0 to compile the code.
by FARID
Sat Sep 02, 2017 3:01 am
Forum: NES Hardware and Flash Equipment
Topic: EPROM LPT Programmer?
Replies: 33
Views: 10170

Re: LPT EPROM Reader?

I want to use 5v from USB and boost it to 12.75v (VPP) and 6.25v (VCC) for programming the EPROM. I found these two chip : MC34063 https://media.digikey.com/Renders/~~Pkg.Case%20or%20Series/8-DIP_sml.jpg LM2577 https://media.digikey.com/renders/Texas%20Instr%20Renders/TO-220-5%20(Straight%20Leads)_4...
by FARID
Thu Aug 31, 2017 10:38 am
Forum: NES Hardware and Flash Equipment
Topic: EPROM LPT Programmer?
Replies: 33
Views: 10170

Re: LPT EPROM Reader?

Are you specifically trying to support programming the 27C801 ? For now I am testing it with AT27C080 It'd be much easier if you didn't. What do you mean? Pin 11 = /S7 = /Wait = /Busy ← inverter ← RC delay from /DataStrobe (should be set to match the ROM's access speed) Pin 14 = /C1 = /DataStrobe =...
by FARID
Wed Aug 30, 2017 12:04 am
Forum: NES Hardware and Flash Equipment
Topic: EPROM LPT Programmer?
Replies: 33
Views: 10170

Re: LPT EPROM Reader?

Now I feel that EPROMr doesn't use the real EPP handshake. It seems that EPROMr (and it's other mods) uses SPP and tries to generate the handshake signals manually by using the software. Here is the summery of the pin function for different projects of EPROMr : EPROMr v1.0 Pin1 ==> Reset Pin14 ==> C...
by FARID
Sun Aug 27, 2017 12:58 pm
Forum: NES Hardware and Flash Equipment
Topic: Schematic for UM6561?
Replies: 30
Views: 26719

Re: Schematic for UM6561?

The datasheet that Farid found for the UM6561 says that pin 19 is P1 D2 (i.e. famicom microphone). If it is Famicom microphone should I connect it GND (as suggested in Russian schematic) or leave it floating? I notice that he switched pin 32 from ground (in the initial pinout) to 5V (in his very fi...
by FARID
Fri Aug 25, 2017 1:22 pm
Forum: NES Hardware and Flash Equipment
Topic: Schematic for UM6561?
Replies: 30
Views: 26719

Re: Schematic for UM6561?

Seems to be the official datasheet of UM6561 :
http://bbs.a9vg.com/thread-5103544-1-1.html
by FARID
Fri Aug 25, 2017 5:11 am
Forum: NES Hardware and Flash Equipment
Topic: Schematic for UM6561?
Replies: 30
Views: 26719

Re: Schematic for UM6561?

muramasa wrote:Thanks for the schematics Farid. I do have a question though can the UM6561 be used in a NTSC system if I select a different crystal?
Sorry I have no idea about it.
But I can test it if you give me the proper info.
by FARID
Sun Aug 20, 2017 3:34 am
Forum: NES Hardware and Flash Equipment
Topic: EPROM LPT Programmer?
Replies: 33
Views: 10170

Re: LPT EPROM Reader?

Well It didn't work! :cry: So this is way too tough than it seems at first even for a simple read operation! Here are some notes I found out from googling : I have to use only EPP mode and not SPP or ECP. Reg5 of Control pin is used for Enabling Bi-directional mode for D0 ~ D7 [pin2 ~ pin9]. So I ha...
by FARID
Fri Aug 18, 2017 10:35 pm
Forum: NES Hardware and Flash Equipment
Topic: EPROM LPT Programmer?
Replies: 33
Views: 10170

Re: LPT EPROM Reader?

Use Atmega32+VUSB instead of crappy old slow LPT with unknown response times. Unless you use pure realtime DOS. I try to keep it in my mind for future projects, but for now I want to keep this thing as simple as possible. That's great Farid!! Unfortunatelly, I don't think this will compile under Li...
by FARID
Fri Aug 18, 2017 12:00 pm
Forum: NES Hardware and Flash Equipment
Topic: EPROM LPT Programmer?
Replies: 33
Views: 10170

EPROM LPT Programmer?

In order to learn some basic info about eprom programmer I want to make this : EPROMr https://web.archive.org/web/20001001132204im_/http://www.zws.com:80/products/epromr1/epread_closeup.gif https://web.archive.org/web/20001001132204im_/http://www.zws.com:80/products/epromr1/eprom_reader.gif It seems...
by FARID
Wed May 24, 2017 6:28 am
Forum: NES Hardware and Flash Equipment
Topic: NES / Famicom controller with Turbo buttons
Replies: 22
Views: 14832

Re: NES / Famicom controller with Turbo buttons

Here you are : UM6582 pinout
by FARID
Fri Mar 31, 2017 4:54 am
Forum: NES Hardware and Flash Equipment
Topic: Emulating the MMC1 with a set of 5 (or 3) PAL22V10
Replies: 28
Views: 9332

Re: Emulating the MMC1 with a set of 5 (or 3) PAL22V10

How about using ATF1504AS which seems to be active CPLD :
44 PIN : TQFP (10x10) / PLCC (16x16)
64 Macrocells
32 IO