From 7bc981af6e2abd669092589ceacfd9b9a38fdb00 Mon Sep 17 00:00:00 2001 From: Erik Kooistra <kooistra@astron.nl> Date: Mon, 30 Jul 2018 14:12:27 +0000 Subject: [PATCH] Added comment on expected DB output size in terms of M9k and M144k block RAM. --- .../src/vhdl/node_apertif_unb1_correlator_output.vhd | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/applications/apertif/designs/apertif_unb1_correlator/src/vhdl/node_apertif_unb1_correlator_output.vhd b/applications/apertif/designs/apertif_unb1_correlator/src/vhdl/node_apertif_unb1_correlator_output.vhd index fcf3739739..2187d4a2f1 100644 --- a/applications/apertif/designs/apertif_unb1_correlator/src/vhdl/node_apertif_unb1_correlator_output.vhd +++ b/applications/apertif/designs/apertif_unb1_correlator/src/vhdl/node_apertif_unb1_correlator_output.vhd @@ -89,6 +89,12 @@ ARCHITECTURE str OF node_apertif_unb1_correlator_output IS SIGNAL src_out_arr : t_dp_sosi_arr(0 DOWNTO 0); -- Output DB + -- . In simulation store: all visibility packets for entire sync interval to avoid need to use DB arm mode. + -- . On hardware store + -- - assume use 8b instead of 9b for M9k and M144k RAM, so effectively M8k and M128k RAM + -- - at least 1 visibility packet to have minimal DB RAM resources of 621 * 32 b which fits in 4 M9K = 4 * 1024 * 8b + -- - all 64 visibility packets per beamlets to have faster M&C access and DB RAM resources 39 * 1024 * 32 b = 1277952b, + -- which fits in 10 M144k, because 10 * 16 * 1024 * 8b = 40 * 1024 * 32 b CONSTANT c_vis_header_size : NATURAL := 21; -- (pad(2) + eth(14) + ip(20) + udp(8) + app_id(16) + app_flags(24)) / 4 = 84 bytes / 4 = 21 words CONSTANT c_vis_payload_size : NATURAL := c_nof_complex*g_nof_visibilities; CONSTANT c_vis_packet_size : NATURAL := c_vis_header_size + c_vis_payload_size; -- = 21 + 600 = 621 -- GitLab