NXP under Interface->Bridges has some ICs that behave as a UART slave and an I2C master and other ones that behave as an I2C slave and a SPI master. If you chained two together you could communicate to a SPI slave using a UART master. BUt I don't know of a single chip that does it all in one.
Another way is you could bit blast maybe using a the GPIO on a UART-slave/I2C-Master IC.
ikalogic: Doable Yes.
I used Parallel port back before my microcontroller days to communicate with SPI and microwire. I see no reason RS232 cannot be implemented.
Is the RS232 from a PC using +-12v levels or from a controlling device using 0-5v levels? Well either way you need to control the outputs TX, RTS, and DTR to emulate the outputs CS, CLK, and DIN. Next control CTS or any other input control lines to emulate DOUT.
?TX? You may be questioning how can TX be used as a control (HI/LO) line when its a dedicated NRZ data line. Haha, there in lies the true challenge. I will not spill the beans on that one. Ever so much more victorious the feeling to solve that challenge own your own in place of being instructed how.
Here is a hint I feel more than suffices. How do you keep a rapidly toggling signal uninhibited at one end and steady DC on the other end? Now once you add additional chips what difference does it make if a micro is used or not. Best to prevent then to patch with glue... logic.
In many respects a PIC programmer is similar to an SPI device, so you could use similar techniques to the JDM type 'serial' programmers - but you're making it hard work by not using a simple PIC to do the job.
Let me clarify my earlier remark. It is easy to do with a microcontroller. Having a UART and an SPI port in the hardware would make the job fairly easy. Having to do one or both in software would be moderately challenging, but not overly difficult. Any "chip" you found that would satify your requirements would probably be a preprogrammed microcontroller in any case.
I was just trying to concentrate on the main point of SPI to UART, if i started speaking about programmers.. i was quite sure the discussion would diverge somewhere far from what i needed.
I was just trying to concentrate on the main point of SPI to UART, if i started speaking about programmers.. i was quite sure the discussion would diverge somewhere far from what i needed.
Let me clarify my earlier remark. It is easy to with a microcontroller. Having a UART and an SPI port in the hardware would make the job fairly easy. Having to do one or both in software would be moderately challenging, but not overly difficult. Any "chip" you found that would satify your requirements would probably be a preprogrammed microcontroller in any case.
I want to build an ISP programmer that attaches to the serial port of a PC.
I have already made a parallel programmer here:
**broken link removed**
But Parallel port is disapearing, slowly but surely, so i want to find a long term solution, either USB or SERIAL. I am able to build any required program (under WINDOWS)
I thought i would start by putting my first target on the SERIAL port (since there exist many USB to serial adapters out there..)