DS90UB953-Q1: The confusing register 0x79 in BIST process with DS90UB954-Q1

Jasper Yao

Part Number: DS90UB953-Q1
Other Parts Discussed in Thread: DS90UB954-Q1, , ALP

Hi there,

I have got an problem with BIST process between DS90UB953-Q1 and DS90UB954-Q1. The BIST process in slides DS90UB953/954 System Design & Operation is shown below. And he predefscripts in ALP of 954 BIST need to read register 0x79 on UB953 which is shown below. But the register 0x79 in UB953 datasheet in reserved. So I can't understand the meaning of reading register 0x79 on UB953 in BIST. Does anyone can give me some help? I will appreciate it very much.

over 4 years ago

0 Vishy Viswanathan over 4 years ago

TI__Mastermind 21685 points

Jasper,

I am checking about this. This BCC Error Status register functionality is explained in the following app document (pages 14 and 18)

https://www.ti.com/lit/pdf/snla267

May be this functionality is covered on the deserializer side and so omitted on the 953 DS. Let me check and get back to you.

Thanks,

Vishy

0 Jasper Yao over 4 years ago in reply to Vishy Viswanathan

TI__Expert 6370 points

Hi, Vishy

I can't find BCC Error Status register on datasheet of 953 DS. Looking forward to your checking and reply.

+1 Vishy Viswanathan over 4 years ago in reply to Jasper Yao

TI__Mastermind 21685 points

Jasper,

The back channel error that is relevant for user is General Status register 0x52[1] (bit 1 back channel CRC error) and so register 0x79 is not public. That's the reason 953 DS is showing it as reserved. I will update predef folder 953-954 BIST script lines in next ALP profile update. Please comment it out for the time being. Also, I will put a request to update the documentation that refers register 0x79.

Thanks,

Vishy

0 Jasper Yao over 4 years ago in reply to Vishy Viswanathan

TI__Expert 6370 points

Thanks for your reply, really appreciate it.

Interface

Interface forum

DS90UB953-Q1: The confusing register 0x79 in BIST process with DS90UB954-Q1