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Re: JTAG - CLK Pin limited to 0.7V
Dear Aiman, Sorry for the delay. I can compile and download the design to the one remaining board without issue, and have done so many times. I am measuring TCK actually on the PCB - PIN1 of the 10 pin header. The actual voltage does depend on the type of USB Blaster used - USB Blaster 2 gets to about 0.7V but others are slightly lower. Many thanks, Adrian3.2KViews0likes0CommentsRe: JTAG - CLK Pin limited to 0.7V
Hello Aiman, Thanks for your response. I have verified multiple times the pull-up and pull-down resistors on the JTAG lines. The TCK signal is clean, crisp and not in any way noisy - but just clipped at 0.7Volts. TCK is pulled low through a 1K resistor. I've tested with 4 cables - a mix of Altera USB Blaster 2, 1 and 3rd party tools. The actual level of the TCK signal changes depending on the cable used, with USB Blaster 2 being the best. Pin 4 is at 1.8V, which is the VCCIO level and VCCPGM level. All rails are as expected - the device exits reset as it is configured for active serial (via MSEL) and I can see it try and load an image from the flash device. As a test I added a 10K pull up resistor to TCK with no download cable attached, and similarly it only goes to 0.7V. Must be a damaged input? How can I have done this by programming with the wrong image? It really was immediate, on 2 boards, after programming with the wrong device selected. Could it have sent one of the reserved JTAG codes? Many thanks, Adrian3.3KViews0likes0CommentsRe: JTAG - CLK Pin limited to 0.7V
Hello Aiman, Thanks for your input. While the certificate had indeed expired, fixing that issue did not solve my problem. This is verified on 3 different PCs with multiple JTAG cables (USB Blaster 1 and 2). Interestingly on one setup doing Autodetect does detect a device but with an unknown ID (UNKNOWN_2EF20DD). Screenshot attached. I have also noticed with USB Blaster 1 the clock gets to about 400mV, and on USB Blaster 2 the clock is about 0.7V. Many thanks. Adrian.3.3KViews0likes0CommentsJTAG - CLK Pin limited to 0.7V
I have 2 x custom boards with 10CX085YU484E6G and a MT25QU01GB flash device that have been working fine. However, for some reason Quartus changed the device and when I last programmed the FPGA and Flash with the wrong image I can now no longer see the device on JTAG. It cannot detect anything on the JTAG chain. I've tried removing the MT25QU010GB device, and when I put a scope on the JTAG clock signal it is clean and square but only gets to at about 0.7V. TDI looks good, but the CLK signal appears clamped. Could I have damaged the JTAG CLK inputs somehow? I've done exactly the same thing on both boards with now get identical behaviour. Any help appreciated.3.4KViews0likes8CommentsRe: Enpirion EM2130L02QI
Hello Mostafa, I think I have found my problems. Firstly the RTUNE resistor was changed to 1K5 from 6K04 and the output of the regulator is stable for much longer. I have 2 devices side by side (one for 0V9 and another for 3V3) and if I disable the 3V3 regulator the 0V9 device works perfectly and is stable and continuous. Long story short it looks like the 3V3 regulator is causing ground instability issues on the 0V9 reg. and I think the 0V9 was shutting down because of this. Unfortunately it means a re-spin. Many thanks.1.7KViews0likes0CommentsRe: Cyclone 10GX VREF pin
Hi, yes all connected to Quartus and the Quartus programmer. I have tried multiple programmers(download cables), including the official Altera USB Blaster 2. I am able to program other devices from Quartus with the same set up and download cable fine. Would floating VREF pins cause this problem? Thanks.1.7KViews0likes2CommentsEnpirion EM2130L02QI
I am using EM2130L929QI to provide 0.9V core voltage for Cyclone 10GX FPGA. The device is turning off after between 2 and 45 seconds. I have another 2130 on the board providing 3.3V and it is working ok. The only difference between the 2 being the voltage output resistors. I have tried to connect to the device via the SPI bus but it does not appear to be communicating. I have isolated the regulator and used a 0.9V ben supply and board is pulling about 250mA on the 0.9V rail which seems reasonable. I'm at a bit of a loss and need to understand why the regulator will turn itself off. Any help appreciated.1.8KViews0likes3CommentsCyclone 10GX VREF pin
I have a custom board using Cyclone 10GX085YU484 and I cannot program the device and it does not appear on the JTAG chain. I have left the VREF pins floating (VREF pins (T7, T13, J15 and F12) ). The datasheet says these should be connected to VCCIO or GND. Could this error stop the FPGA from running up and being programmed (visible on JTAG)? Same with VREFP_ADC and VREFN_ADC (floating and should be GND). Thanks.1.8KViews0likes4CommentsCyclone 10GX JTAG Issues and 2130L020QI problems
I have a custom board based around Cyclone 10CX085yU484 with Empirion 2130L020QI regulator providing 0.9V core rail. After 10 to 40 seconds the regulator is switching off. Using a bench 0.9V power supply, the FPGA is not responding to the JTAG. In desperate need of help from apps engineer, very close to redesigning PCB without 2130 and with a Xilinx part. How do I go about talking to an apps engineer? Anyone know of a phone number?936Views0likes1Comment