SAP FI-MM-SD INTEGRATION

The link between SD and MM :-
1. When you create sales order in SD, all the details of the items are copied from Material master of MM.
2. MRP and availability check related data is also taken from MM although you control this data in SD also.
3. While you create inbound/outbound delivery with reference to a sales order, the shipping point determination takes place with the help of the loading group, plant data, shipping conditions etc. This also refers to Material Master.
4. The material which you are entering in a sales order must be extended to the sales area of your sales order/customer otherwise you cannot transact with this material.
There are many such links between SD and MM.  
Now the link between SD and FI :-
1. Whenever you create a delivery with reference to a sales order, goods movement takes place in the background. eg. In case of standard sales order, you create an outbound goods delivery to the customer.
Here movement 601 takes place. This movement is configured in MM. Also, this movement hits some G/L account in FI. Every such movement of good s hits some G/L account.
2. The accounts posting in FI is done with reference to the billing documents (invoice, debit note, credit note etc) created in SD. Thus this is a link between SD and FI
3. Tax determination: In case of a tax determination also, there is a direct link between SD and MM
SD Integration points with other modules
SD module is highly integrated with the other modules in SAP.

FI-MM Integration
Transaction code : OBYC (in easy access)
In this transcation we have to specify GL account codes for material valuation created by MM consultants.
The process in MM is herebelow,
1) Purchase Order : Tr code ME21N - here no integration required with FI
2) Goods Issue : Tr Code MIGO - here no integratinwith FI
3) Invoice Reciept - Tr Code MIRO - here when the invoice is recieved & MM process the transaction based on OBYC configuration system will generate FI document. System also generates Material document as well
4) Payment : Tr code F110 - Here also the the transcation affects FI

FI-SD integation:
This integration done using Tr Code VKOA. here we have to define GL account codes to Condition types.
Process
1) SD Raises Sales Order - No implication in FI
2) SD raises Delivery doc - No implication in FI
3) SD processes billing - no implication in FI
4) SD releases billing doc to FI - FI document gets generated (Tr Code VFX3)