sim_scan hardware [Archive]

tester_v

06-09-2003, 01:43

I saw people having problems building(using) simscan hardware. I built it yesterday and first it didn't work until i powered the board from an external power supply (actually I hate com powered stuff, and found that normal) Then i decided to optimize schematics and remove the whole bunch of no longer needed transistors but the thing didn't work anymore. I got a lot of "Card don't send Answer To Reset" and "Bad data in Answer To Reset" messages. Finally I found it was a timing problem and you can't make it work without the 470uF capacitor at DTR & RTS lines, discharged exactly by a 10 kOhm resistor. Everything else works just fine. I tried some other ICs like 74HC14 (one from TI worked, and one from Philips didn't work).
Also make sure the oscillator is working at the right frequency. I used 6.1440 MHz. Hope this help someone. Good luck! :-)

besi_al

06-09-2003, 02:29

Please Tester_v can you give me the schematics?

wssiow

06-09-2003, 04:04

yes, u r right. i also power up with external battery.

but how about the dejan's programmer that write the PIC? have u build it? i fail to run it.

tq

Alf

06-09-2003, 21:20

Perhaps I should stick a simple phoenix (for KI extraction and external eeprom programming) and a JDM (for programming PIC) schematics...

tyuyung

06-10-2003, 00:12

images and schematics:

http://www.simprog.narod.ru/

Alf

06-10-2003, 00:21

Thanks for saving me trouble :)

wssiow

06-10-2003, 03:51

@ all

is there any replacement for IC MAX232? i can't buy it in my country.

i find very hard to get the schematic that no need to use "MAX232" IC.

:)

tq...

yuge

07-18-2003, 03:31

here ,,,,http://carddiy.welcometextiles.com/Simple%20Phoenix%20sch2.gif

it is a phoenxi schematic no MAX232 in it, it work correctly.

wssiow

07-18-2003, 05:25

still have someone study old message ya... :)

tq very much...