Does EZ-Serial disable SWD on PSoC4 BLE?

Tip / Sign in to post questions, reply, level up, and achieve exciting badges. Know more

cross mob
Renate
Level 3
Level 3
25 replies posted 25 sign-ins 10 replies posted

I'm having a lot of problems getting SWD to work with PSoC4 BLE (CYBLE-012011-00 module).
If I do a reset and a SWJ_SEQUENCE (line reset) and a SWJ_TRANSFER (ID query) quickly I can get a correct ID (0x0bb11477).
I can repeat that SWJ_TRANSFER but after about 9 milliseconds after reset goes high, the transfer fails for having no data asserted from the module with an SWD code of 0x07.
This works 100% reliably, reset, SEQUENCE, eleven TRANSFERs, then the twelveth TRANSFER fails.
Is this module booting up on EZ-Serial and by 9 milliseconds in EZ-Serial has killed the SWD pins?
This is a brand new, sealed module bought from a big US supplier.
What's the easiest way to get rid of EZ-Serial? I'm thinking of using a hammer at this point.

0 Likes
1 Solution
Renate
Level 3
Level 3
25 replies posted 25 sign-ins 10 replies posted

In short, yes, EZ-Serial if not "acquired" within the 2mS limit will run off by itself and at approximately 9mS will have gotten as far as repurposing/disabling the SWD.

You do have these 9mS to configure the port and erase EZ-Serial even if the 2mS "acquire" limit is too tight for your particular circumstances. Once EZ-Serial is gone you can flash it with your own code that leaves SWD open all the time, making life simpler for you.

View solution in original post

0 Likes
3 Replies