ISO 7816 using UART

RE: ISO 7816 using UART

user85723 — Tue, 14 Jun 2022 19:36:59 GMT

Hello! Now I have the same task. The Nordic chip looks like an ideal option in terms of connectivity, but it needs (just like you 5 years ago=0) ISO 7816 support. Please let me know if you managed to implement this?

RE: ISO 7816 using UART

user15146 — Thu, 21 Sep 2017 08:07:53 GMT

You could maybe use PPI and toggle the GPIO with the GPIOTE on the UART events( i.e. EVENTS_RXDRDY and EVENTS_TXDRDY)

RE: ISO 7816 using UART

user21573 — Tue, 19 Sep 2017 14:31:28 GMT

How do I synchronize a manually generated clock signal on a clock line with the data that is transferred on the I/O line via an existing UART driver?

RE: ISO 7816 using UART

user4908 — Thu, 14 Sep 2017 18:48:06 GMT

You won't make any bitbanging thing work with BLE stack active. It runs with higher priority and will take time to process the event which can take as long as several milliseconds. So you will need to make ISO7816 work with DMA enabled HW UART block as is (which is unlikely) or do it only at the moment when stack is inactive. Which should be possible because your will be master talking to secure element when you want... with some challenges (like long processing on SE side) of course. There is also time-slot API in Nordic BLE stack which can help you to get guaranteed interval without interrupting by the stack (with some drawbacks to throughput of course, see the documentation).

RE: ISO 7816 using UART

user21573 — Thu, 14 Sep 2017 15:11:44 GMT

Just tried generating the clock signal on the clock line. Doesn't work with a SoftDevice present. What do I need to change to make that work?