GPRS_Components: add RA definition for single block packet access

Change-Id: I8997121f1b1207d4236f5911befc3c29278f37d8
diff --git a/pcu/GPRS_Components.ttcn b/pcu/GPRS_Components.ttcn
index 2a8726f..f48eae1 100644
--- a/pcu/GPRS_Components.ttcn
+++ b/pcu/GPRS_Components.ttcn
@@ -651,7 +651,9 @@
 }
 
 /* One phase packet access (see 3GPP TS 44.018, table 9.1.8.1) */
-const BIT8 chan_req_def := '01111000'B;
+const BIT8 chan_req_def := '01111000'B; /* 01111 { 0xx | x0x | xx0 } */
+/* Single block (two phase or RR signalling) packet access */
+const BIT8 chan_req_sb  := '01110000'B; /* 01110xxx */
 
 /* Establish an Uplink TBF by sending RACH.ind towards the PCU */
 function f_pcuif_tx_rach_rx_imm_ass(uint16_t ra := bit2int(chan_req_def),
diff --git a/pcu/PCU_Tests.ttcn b/pcu/PCU_Tests.ttcn
index 8facde7..dffbc4d 100644
--- a/pcu/PCU_Tests.ttcn
+++ b/pcu/PCU_Tests.ttcn
@@ -1132,8 +1132,8 @@
 	var uint32_t unused_fn;
 	var GprsMS ms;
 
-	/* 0111 0xxx: Single block packet access; one block period on a PDCH is needed for two phase packet access or other RR signalling purpose. */
-	var uint16_t ra := oct2int('70'O);
+	/* Single block (two phase) packet access */
+	var uint16_t ra := bit2int(chan_req_sb);
 	if (g_force_two_phase_access) {
 		/* If 2phase access is enforced by the network, then let's
 		   request a One phase packet access, we'll receive a single block