SHA1 salted hash

Just feed it the HASH_SHA1 constant as the algorithm to use.  Do you need a HMAC or a simple HASH?

developer.garmin.com/.../Cryptography.html

I need a salted HASH indeed, not HMAC so the function I provided might not be the one to choose. The normal hash function Toybox.Cryptography.Hash (garmin.com) does not seem to include a salt. Any ideas on how to do that?

Mark_v_E said:

 The normal hash function Toybox.Cryptography.Hash (garmin.com) does not seem to include a salt. Any ideas on how to do that?

Hopefully I'm not missing something here, but a salt is just additional data added to the message to be hashed, so I don't think the API needs to support a salt parameter. You just take the input data and add the salt to it before hashing. (For various reasons, it's usually recommended to append the salt to the data.)

Indeed and crypto random bytes can be used to generate a suitable cryptographically sound salts to use.

Sorry I was wrong here in my info. I checked the docs of the API I try to access and it needs an HMAC SHA1 based signature and not a normal HASH. The JAVA equivalent function for this is HmacSHA1Encrypt(String encryptText, String keySecret). 

Then use random bytes, convert into a base 64 encoded string to create a salt. Then add salt to end of string fed into HMAC.  Send salt with HMAC output to enable message authentication other end.