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VCF 6502 BADGE V1 - how to enter BASIC

1ST1

Veteran Member
Joined
Oct 21, 2014
Messages
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Location
near frankfurt/m, germany
Hello, I have a VCF 6502 Badge V1 and basically now it works, I also can communicate with it using for example Putty. So I get a prompt and I can say

S HELLO WORLD

and it will display the text on the LED display.

With the instruction @ it should jump into BASIC, but it does not. It's still in the monitor program. What's wrong?

>?
Commands are :
Syntax = {} required, [] optional, HHHH hex address, DD hex data

[HHHH][ HHHH]{Return} - Hex dump address(s)(up to 16 if no address entered)
[HHHH]{.HHHH}{Return} - Hex dump address range (16 per line)
[HHHH]{:DD}[ DD]{Return} - Change data bytes
[HHHH]{G}{Return} - Execute a program (use RTS to return to monitor)
{HHHH.HHHH>HHHH{I}{Return} - move range at 2nd HHHH down to 1st to 3rd HHHH
[HHHH]{L}{Return} - List (disassemble) 20 program lines
[HHHH]{.HHHH}{L}{Return} - Dissassemble range
{HHHH.HHHH>HHHH{M}{Return} - Move range at 1st HHHH thru 2nd to 3rd HHHH
[HHHH][ HHHH]{Q}{Return} - Text dump address(s)
[HHHH]{.HHHH}{Q}{Return} - Text dump address range (16 per line)
{S}[up to 32 text characters]{Return} - Set 32 byte LED message
[HHHH]{U}{Return} - Upload File from PC to SBC (Xmodem/CRC)
[HHHH.HHHH]{X}{Return} - Download File from SBC to PC (Xmodem/CRC)
{V}{Return} - Monitor Version
{P*}{Return} - Protected Power Down
{!}{Return} - Enter Assembler
{@}{Return} - Cold-Start EhBASIC
{#}{Return} - Warm-Start EhBASIC
{?}{Return} - Print commands


>@
65C02 Monitor v5.2 (2-24-18)
with EhBASIC (c) Lee Davison
(Press ? for help)
>S TEST TEST TEST
>
 
It works just fine when I try it on my badge. I get a memory size question and hitting the enter key gets me to a ready prompt.

Possible things to check: Did the ROM contents somehow get corrupted? Are all the address pins on the ROM properly in the socket? Is there a bad solder connection on one of the high address pins? Are the jumpers on the board set correctly to match the type of ROM you have?
 
Missing the U jumper would explain the problem.
The fact that it ran the monitor was enough to verify that the data bus was correctly working. It also indicates that at least a large part of the addressing is working. My immediate suspicion was one of the high address bits stuck, which would mean that the jump to BASIC ended up jumping to somewhere in the monitor instead.
Missing the U jumper means that A14 on the ROM is floating, that usually means it reads as high. The effect of this is to make the lower half of the ROM unreadable. Any reads from that area gets the data from the upper half of the ROM instead, and the monitor program is at a much higher address than BASIC is.
 
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