On 6/26/2010 2:14 AM, Magnus wrote:
Yo!The 1804/5/6 are slightly improved versions of the 1802. Depending on the particular model, they have internal ROM, RAM, a timer, and some new instructions. They were intended for single-chip microcontroller applications, where you ordered them with your program already in the internal ROM.
Not much code was written to use the new instructions. The internal ROM is useless for general purpose applications; it is typically disabled so you can use it with external memory chips instead.
The only thing missing in the 1804/5/6 that the 1802 has is the LOAD mode. Unfortunately, LOAD is used in the Elf computers for their front panel interface.
I bought some 1805's on eBay for a good price. If you'd like to experiment, I'd be happy to swap one for an 1802.
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