Can't connect to PostgreSQL in Rstudio, possible permissions issue?

[doeehunt]

I've followed the documentation on db.rstudio.com and other sites, and I'm not able to connect to my Postgres database from Rstudio. I'm on macos 10.14. Running:

con <- DBI::dbConnect(odbc::odbc(),
                       Driver = "PostgreSQL Driver",
                       Database = "mydatabase",
                       UID = "myuser",
                       PWD = "mypassword",
                       Host = "localhost",
                       Port = 5432)

Gives the error:

Error: nanodbc/nanodbc.cpp:983: 00000: 

At first, I got an empty list when running odbcListDrivers(), however I was able to get it to show the postgres driver location/value by copying odbcinst.ini from the global /etc to my user (cp /etc/odbcinst.ini ~/.odbcinst.ini).

Similarly, odbcListDataSources() returned nothing until I did the same thing (cp /etc/odbc.ini ~/.odbc.ini)

The odbc.ini and odbcinst.ini are locked from editing via Finder, but can be edited via nano/terminal.

I also tried to solve the problem by installing the database drivers via Postgres' stack builder. This has left a file called postgres-reg.ini in /etc containing:

[PostgreSQL/12]
InstallationDirectory=/Library/PostgreSQL/12
Version=12.1-3
Shortcuts=1
DataDirectory=/Library/PostgreSQL/12/data
Port=5432
ServiceID=postgresql-12
Locale=C
Superuser=postgres
Serviceaccount=postgres
Description=PostgreSQL 12
Branding=PostgreSQL 12
SB_Version=4.1.0
pgAdmin_Version=4.16
CLT_Version=12.1.3
[psqlODBC]
Description=ODBC drivers for PostgreSQL Server, packaged by EnterpriseDB.
InstallationDirectory=/Library/PostgreSQL/psqlODBC
Version=12.01.0000-1
Branding=Postgres Plus Add-ons

I tried using the InstallationDirectory, specified in this file, in the odbc.ini file, but that didn't change anything.

Overall I'm suspecting that it's a permissions issue, but I'm not quite sure where to look next.

Thanks for your help!