Oh no, not another computer museum - COMX35

COMX35

A contemporary of the C64. One of the main selling arguments was that the processor was used in the space shuttle. An RCA 1802. Note the small funny joystick right of the keys.

Technical data
(preliminary)

Components:

CDP1802ACE
CDP1869CE
CDP1870CE
CDP1871ACE

Processor pins on Expansion bus:

 1 - MA1     2 - MA0
 3 - MA2     4 - 
 5 - MA4     6 - MA3
 7 - MA5     8 - MA6
 9 - MA7    10 -
11 - *MWR   12 - 
13 - IPB    14 - 
15 - EF4    16 - 
17 - SC1    18 - SC0
19 - *WAIT  20 - CLOCK
21 -        22 - *INTERRUPT
23 - N1     24 - N2
25 - IPA    26 - N0
27 - *CLEAR 28 - *MRD
29 -        30 - Q
31 - BUS6   32 - BUS7
33 - BUS4   34 - BUS5
35 - BUS2   36 - BUS3
37 - BUS0   38 - BUS1
39 - Vcc    40 - 
41 -        42 - 
43 - Vss    44 - Vss
 * = Active low
ROM dump Eary 2008 I devised a way to dump the ROMs without soldering them out or make a custom interface for the COMX. By dumping the ROM in parts to a variable and write that variable to tape (DSAVE command), all that was needed was a WAV to BIN converter. Written in Perl.

Power supply ratings:
9V DC, 800 mA max., pin is plus.

Want to build your own 1802 processor system, like the COSMAC ELF? Now there is an opportunity to get a 1802 processor cheaply, including two CDP1823 chips (128 x 8 bits). Look here.

Generic links:


Last updated: 2013-05-09

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