Getting started resources for MAX 7000

If you are not using any clocked FFs then you don't need a clock source and can operate purely combinatorial logic.

For sure you need to understand the max current drive limits for the I/Os. Datasheet will tell you the limits.

The 7000A series is 3.3V supply and I/O voltage, but the I/Os are 5V tolerant. So you can add a pullup to +5V tied to an output if need be.

JTAG is its own protocol (NOT the same as UART/SPI/I2C). So unless you have a JTAG knowledgeable master (like an Altera ByteBlaster) you will have to connect the JTAG pins to standard I/O ports on your micro, and then write the code that simulates the JTAG protocol. Be aware however that writing the code on a micro that does low level JTAG (ie, bit banging TCK/TMS/TDI/TDO correctly) is just a very small part of the problem. Writing all the code that implements full device programming thru JTAG is a whole other significant project. Old Altera used to supply source code for such a function (the old JAM STAPL player) but I don't know if that is still around now that Intel has assumed control.

Personally I would recommend getting an Altera USB Blaster clone (Terasic has a nice one that is 100% Altera compatible that is inexpensive).