10 Replies Latest reply on Feb 1, 2018 4:07 PM by pach_1977636

    Looking for a faster alternative to CY8C4247LQI-BL483

      Hi folks,


      I am working on a project to add some functionality to an old 8-bit processor-based computer. I started a prototype using the Pioneer PROC/PSOC 4 kit. Basically, where I'm at, is that it almost works. The 48Mhz processor is just a hair too slow to directly emulate RAM when interfacing with the processor. What I mean by that is that I can write data from the computer to the PSOC, and I can read data back out, and I can even run machine language code from the PSOC's RAM... but this last bit works for only about 30 seconds or so of looping through a few bytes of code before something isn't ready quite in time and things crash.


      One option would be to add dual-port RAM as an interface between the two busses, but that add a lot of complexity and cost to my solution.


      I think that the newer 80Mhz MCUs would be fast enough, since 48Mhz is pretty darn close.


      So, what I'm looking for is recommendations on whether there are newer devices that are otherwise pretty similar to what I've been using. I'd prefer something with a BLE antenna on-board or in a small prototype module. The main other requirement is to be able to interface with a 5V CMOS TTL bus. The PROC and PSOC 4 devices do this well.



        • 1. Re: Looking for a faster alternative to CY8C4247LQI-BL483

          Hmm... I was thinking that there were faster PSoC or PRoC devices similar to what I am using, but now I'm not so sure. May have to look at switching to ST or TI. TI, for instance, has a 48MHz core M3 device. That should be about 50% effectively faster than this 48Mhz core M0....


          I'd rather not switch, though. Lots of new lessons to relearn and prototype wiring to redo....

          • 2. Re: Looking for a faster alternative to CY8C4247LQI-BL483

            Have a look at PSoC 6 3. This has an ARM M4 CPU running at up to 150 MHz and a M0 CPU. Should be quite enough. See preliminary datasheet.



            • 3. Re: Looking for a faster alternative to CY8C4247LQI-BL483

              Looks plenty fast and powerful, but doesn't look like it will interface directly with a 5V bus.

              • 4. Re: Looking for a faster alternative to CY8C4247LQI-BL483

                I'd still like to stick with Cypress. I like the UDB functionality, and the integrated BLE. It's looking, though, like something from NXP might be more in-line with what I'm trying to do. The KE15Z is 72MHz core M0+, and comes in an Arduino footprint prototype kit. I'll have to make new interface cables for my development rig (currently I'm connecting to the CY8CKIT-042 module connectors), and maybe add some external logic to make up for the lack of UDBs, but I think this might work.


                I also looked at the PSOC 5 options. They sound similar, but the expandable proto kit is relatively expensive compared to NXP. I may try the CY8CKIT-050, though, since it doesn't seem like I'll find a PRoC solution that's fast enough anyway.


                What I'd really like is a 48MHz+ core M0+ PRoC 4 option with at least 31 GPIOs.

                • 5. Re: Looking for a faster alternative to CY8C4247LQI-BL483

                  Hello Paul,


                  Unfortunately there is no PRoC/PSoC 4 chip above 48 Mhz. You may use PSoC6 with appropriate level translator to work with 5V bus. PSoC 5 solution may not be suitable as you need integrated BLE too. PSoC6 on the other hand have BLE, UDB and faster clock which meets all your requirements.


                  Best Regards,

                  • 6. Re: Looking for a faster alternative to CY8C4247LQI-BL483

                    There is a cheaper eval board that is expandable from Sparkfun for $49. It has the CY8C5888AXQ-LP096 on board which is an 80Mhz M3 core.  Also, there are 24 UDBs and better analog performance with a 20bit Delta-Sigma ADC and a 0.1% VREF on board. There is a lot more analog routing as well.  Here is the link to the Sparkfun board.


                    Mike Roberts

                    Arrow Cypress Specialist

                    • 8. Re: Looking for a faster alternative to CY8C4247LQI-BL483

                      Level conversion for about 24 lines looks to be a lot more work, expense, and real estate than adding BLE or some other wireless to a PSoC 5. The total space for my solution is about 1 square inch, double-sided but not more than maybe 1/4" thick. Since I can't seem to find a faster, built-in-wireless, 5V-capable MCU, the PSoC 5 looks like the closest-to-ideal choice.


                      I've ordered a CY8CKIT-059, and will see whether it's fast enough to do the memory emulation reliably - I would hope it is, at about 3X the effective speed of the CY8C4247LQI-BL483.  I f so, then I'll start tacking on the other features I want, like wireless and an SD slot. It's cheap enough for the eval board, and just means a bit more soldering to hook it up to the device's test connector.


                      Mike, thanks for the pointer on the Sparkfun PSoC 5 board.

                      • 9. Re: Looking for a faster alternative to CY8C4247LQI-BL483

                        Just a bit of an update on this: I finally got around to wiring up my PSoC 5 kit. I had to remove the LED and the CMOD and SAR capacitors from the CY8CKIT-059 board, as these were in the middle of sets of GPIOs I needed for my buses. After that, it initially did not seem to work well, but after updating to 72MHz, the MCU does seem fast enough to emulate RAM directly for the CPU of the pocket computer.


                        I do have a problem with PSoC Creator always dropping back to 24MHz, though. It does not seem to save the PSoC 5 clock information with the project.


                        Anyway, so far, pretty good, and with about 10 spare GPIOs as well. Next step is to try to get an EmFile SD card interface working, and then probably to see what BLE or WiFi I can adapt.

                        • 10. Re: Looking for a faster alternative to CY8C4247LQI-BL483

                          Got the main bugs worked out of my PSoC 5 project. Basically had to create a new project and copy things over, as I must have messed something up when retargeting. Got it working reliably for the CPU/MCU interface under PSoC 5 at 48MHz, then created a new PSoC 4 project using the same solution. At 48MHz on CY8C4247 it's glitchy. So this does seem to confirm that I need the extra speed of the Cortex M3.


                          For BLE, it's looking like the easiest solution might be to have both a CY8C5888 and CYBLE-214009, and use the PSoC 4 device over SPI or I2C just for BLE. The other options I'm seeing so far are either more expensive, harder to find, bigger, don't have any firmware, or some combination of these.