Know that with a discount there is MORE interest than with a premium.
This is the same whether the point of view is as the issuer or Investor. The calculation (second poster) is also the same.
The differences lie in the journal entries. From an issuer: Dr Cash (selling price); Cr Bond Payable (face amnt); Dr/Cr Discount/Premium on Bonds. Selling price equals = (Face x PV$1) + (Face x Stated int x mo/12 x PVOA). Discount or Premium depends on how you need to balance the formula.
For the Investor, you are paying cash. So that's a credit to cash to decrease the asset. Debit to Investment in Bonds. The figure is the same selling price value.
Like I said above, remember that discount situations yield more interest. For issuer, Dr Int Expense (expense is most often debits; Carrying Amount of Bond x MARKET int rate x mo/12). Credit Cash (ALWAYS same each int PMT for this bond: Facebook Value x STATED int rate). Dr/Cr Discount or Premium to plug.
For Investor: Debit Cash for the int check; opposite side of cash entry for issuer. Credit Interest Income; again, opposite side of the interest expense entry for issuer but this is income. Balance with discount or Premium.
The fun begins when you have to issue between dates. Essentially, you're assuming the seller will charge for the accrued interest from last int date until date of sale.
For Investor: (1) Debit Cash bc you're getting cash. That is a total figure or a plug. Credit Bond Payable for the face amount (sound familiar so far?). Credit Interest Payable (face x int rate x #mos after prev int date/12).
(2) Debit Int Exp (face x int x mo/12). Debit Int Pay (pay back int from (1)). Credit Cash (plug). Then proceed as if transacted on the interest date.
Lastly, if you have to REtire think REverse the original journal entry. eg if Bond is called.
That should be enough. Hope this helps.