Changes between Version 6 and Version 7 of Writing Rules/Tlmt

Timestamp:

Dec 25, 2007, 2:03:30 PM (16 years ago)

Author:

alain

Comment:

--

Writing Rules/Tlmt

@@ -18 +18 @@
 = B) Single VCI initiator and single VCI target =
 
-Figure 1 presents a minimal system containing one single initiator, and a single target. In the proposed example, the initiator module doesn't contains any parallelism, and can be modeled by a single SC_THREAD, describing a single PDES process. The activity of the '''my_initiator ''' module is described by the SC_THREAD '''execLoop()''', that contain an infinite loop. The variable '''m_time''' represents the PDES process local time.
+Figure 1 presents a minimal system containing one single initiator, and one single target. In the proposed example, the initiator module doesn't contains any parallelism, and can be modeled by a single SC_THREAD, describing a single PDES process. The activity of the '''my_initiator ''' module is described by the SC_THREAD '''execLoop()''', that contain an infinite loop. The variable '''m_time''' represents the PDES process local time.
 
 Contrary to the initiator, the target module has a purely reactive behaviour. There is no need to use a SC_THREAD to describe the target behaviour : A simple method is enough. 
@@ -26 +26 @@
 = C) Initiator Modeling =
 
-In the proposed example, the initiator module is modeled by the '''my_initiator''' class. This class inherit the '''BaseModule''' class, that is the basis for all TLM-T modules. As there is only one thread in this module, there is only one member variable '''time''' of type '''tlmt_time'''. This object can be accessed through the '''getTime()''', '''addTime()''' and '''setTime()''' methods. 
+In the proposed example, the initiator module is modeled by the '''my_initiator''' class. This class inherit the '''!BaseModule''' class, that is the basis for all TLM-T modules. As there is only one thread in this module, there is only one member variable '''time''' of type '''tlmt_time'''. This object can be accessed through the '''getTime()''', '''addTime()''' and '''setTime()''' methods. 
 
 The '''execLoop()''' method, describing the initiator activity must be declared as a member function of the '''my_initiator''' class. 
 
-Finally, the class '''my_initiator''' must contain a member variable '''p_vci''', of type '''VciInitiatorPort'''. This object has a template parameter <'''vci_param'''> defining the widths of the VCI ADRESS & DATA fields.
+Finally, the class '''my_initiator''' must contain a member variable '''p_vci''', of type '''!VciInitiatorPort'''. This object has a template parameter <'''vci_param'''> defining the widths of the VCI ADRESS & DATA fields.
 
 == C.1) Sending a VCI command packet ==
@@ -84 +84 @@
 == C.3) Initiator Constructor ==
 
-The constructor of the class'''my_initiator''' must initialize all the member variables, including the VCI port. The '''rspReceived()''' call-back function being executed in the context of the thread sending the response packet, a link between the '''p_vci''' port and the call-back function must be established. Moreover, the '''p_vci''' port must contain a pointer on the initiator local time.
-The VciInitiatorPort constructor must be called with the following arguments:
+The constructor of the class'''my_initiator''' must initialize all the member variables, including the '''p_vci''' port. The '''rspReceived()''' call-back function being executed in the context of the thread sending the response packet, a link between the '''p_vci''' port and the call-back function must be established. Moreover, the '''p_vci''' port must contain a pointer to the initiator local time.
+The '''!VciInitiatorPort''' constructor must be called with the following arguments:
 {{{
 p_vci(“vci”, this, &my_initiator::rspReceived, &m_time);
@@ -163 +163 @@
 = D) Target Modeling =
 
+In the proposed example, the target handle two types of command : a read burst of 8 words, and a write burst of 8 words. To simplify the model, there is no error management.
+
+The class '''my_target''' inherit the class '''!BaseModule''', that is the basis for all TLM-T modules. The class '''my_target''' contains a member variable '''p_vci''' of type '''!VciTargetPort'''. This object has a template parameter <'''vci_param'''> defining the widths of the VCI ADRESS & DATA fields.
+
 == D.1) Receiving a VCI command packet ==
 
+To receive a VCI command packet, a call-back function must be defined as a member function of the class '''my_target'''. This call-back function (named '''cmdReceived()''' in the example), will be executed each time a VCI command packet is received on the '''p_vci''' port. The function name is not constrained, but the arguments must respect the following prototype:
+{{{
+void  cmdReceived(vci_cmd_t  *cmd,
+               sc_time  time)
+}}}  
+For the read and write transactions, the actual data transfer is performed by this '''cmdReceived()''' function.
+To avoid multiple data copies, only the pointer on the initiator data buffer is transported in the VCI command pacquet (source buffer for a write transaction, or destination buffer for a read transaction).
+
 == D.2) Sending a VCI response packet ==
 
+To send a VCI response packet the '''cmdReceived()''' function must use the '''rspSend()'' method, that is a member function of the class '''VciTargetPort''', and has the following prototype:
+{{{
+void  rspSend( vci_rsp_t *cmd,  
+           sc_time time)        
+}}}
+For a reactive target, the response packet date is computed as the command packet date plus the target intrinsic latency.
+
 == D.3) Target Constructor ==
 
-== D4) TLM-T target example
+The constructor of the class'''my_target''' must initialize all the member variables, including the '''p_vci''' port. The '''cmdReceived()''' call-back function being executed in the context of the thread sending the command packet, a link between the '''p_vci''' port and the call-back function must be established. 
+The '''!VciTargetPort''' constructor must be called with the following arguments:
+{{{
+p_vci(“vci”, this, &my_initiator::cmdReceived);
+}}}
+  
+== D.4) TLM-T target example ==
  {{{
 template <typename vci_param>