{ "guild": { "id": "1361349522684510449", "name": "wafer.space Community", "iconUrl": "2026-06_media/fb143eaa45770cbb40493d09b625e98b-09FD1.png" }, "channel": { "id": "1409664140196188251", "type": "GuildTextChat", "categoryId": "1409664731760955403", "category": "\uD83D\uDCD0 - Designing", "name": "\uD83D\uDCBB-digital", "topic": null }, "dateRange": { "after": "2026-05-31T23:59:59.999+00:00", "before": "2026-07-01T00:00:00+00:00" }, "exportedAt": "2026-07-08T07:24:13.829405+00:00", "messages": [ { "id": "1511801096606187674", "type": "Default", "timestamp": "2026-06-03T18:37:49.337+00:00", "timestampEdited": null, "callEndedTimestamp": null, "isPinned": false, "content": "Having an inverter at the output of a logic cell (buffering the internal node) is almost a given, right?\nSo any custom gates in any static logic family I have to draw I should expect to use an inverter as an output buffer after the actual gate itself, right?", "author": { "id": "262706220073222144", "name": "namibj", "discriminator": "0000", "nickname": "namibj", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/f885abc0dddd0a33e4d4991b3c99091d-7ACD2.png" }, "attachments": [], "embeds": [], "stickers": [], "reactions": [], "mentions": [], "inlineEmojis": [] }, { "id": "1511804973686456542", "type": "Default", "timestamp": "2026-06-03T18:53:13.705+00:00", "timestampEdited": null, "callEndedTimestamp": null, "isPinned": false, "content": "Sometimes you'll find `_0` variants of gates where it's directly the internal output but yeah that's rate and not that useful for general P&R where you'd almost always have an inverter at the output ... except if the cell in question is an inverter or a delay cell .", "author": { "id": "596068704471482370", "name": "246tnt", "discriminator": "0000", "nickname": "tnt", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/88d17af9d19ab43565b0c46751ef7d12-DFEE5.png" }, "attachments": [], "embeds": [], "stickers": [], "reactions": [ { "emoji": { "id": "1184281983791136778", "name": "ferrisCatOwO", "code": "ferrisCatOwO", "isAnimated": false, "imageUrl": "2026-06_media/1184281983791136778-8D756.png" }, "count": 1, "users": [ { "id": "262706220073222144", "name": "namibj", "discriminator": "0000", "nickname": "namibj", "color": null, "isBot": false, "avatarUrl": "2026-06_media/f885abc0dddd0a33e4d4991b3c99091d-7ACD2.png" } ] } ], "mentions": [], "inlineEmojis": [] }, { "id": "1512006127766999142", "type": "Reply", "timestamp": "2026-06-04T08:12:32.575+00:00", "timestampEdited": null, "callEndedTimestamp": null, "isPinned": false, "content": "No. CMOS standard cells have NAND2 and AOI amd OAI cells that don't have inverter at the end and these cells will be used quite a lot in the synthesized netlist.", "author": { "id": "728516105680846892", "name": "chips4makers", "discriminator": "0000", "nickname": "Chips4Makers aka Staf Verhaegen", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/2649a6faac7843086b3d82b1d8f657a3-81998.png" }, "attachments": [], "embeds": [], "stickers": [], "reactions": [], "mentions": [ { "id": "262706220073222144", "name": "namibj", "discriminator": "0000", "nickname": "namibj", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/f885abc0dddd0a33e4d4991b3c99091d-7ACD2.png" } ], "reference": { "messageId": "1511801096606187674", "channelId": "1409664140196188251", "guildId": "1361349522684510449" }, "inlineEmojis": [] }, { "id": "1513203614556885073", "type": "Default", "timestamp": "2026-06-07T15:30:55.674+00:00", "timestampEdited": null, "callEndedTimestamp": null, "isPinned": false, "content": "I just noticed the SRAM behavioral model has timing constraints (55.6 ns, ~18MHz). Do we know if this is a real limit of the SRAM, or just a quirk of the fab's sram model?", "author": { "id": "384390069412429834", "name": "polyfractal", "discriminator": "0000", "nickname": "BreakingTaps", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/8d8c1d8b8ad51d6cdb1a47512c39b297-42908.png" }, "attachments": [], "embeds": [], "stickers": [], "reactions": [], "mentions": [], "inlineEmojis": [] }, { "id": "1513277466205098064", "type": "Reply", "timestamp": "2026-06-07T20:24:23.279+00:00", "timestampEdited": null, "callEndedTimestamp": null, "isPinned": false, "content": "That seems close to the 1.8V figures on https://gf180mcu-pdk.readthedocs.io/en/latest/IPs/SRAM/gf180mcu_fd_ip_sram/cells/gf180mcu_fd_ip_sram__sram512x8m8wm1/gf180mcu_fd_ip_sram__sram512x8m8wm1.html", "author": { "id": "691780627338625077", "name": "rebelmike", "discriminator": "0000", "nickname": "RebelMike", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/49aaff687e56f04e7bbdedf0077bab75-7DDB4.png" }, "attachments": [], "embeds": [], "stickers": [], "reactions": [], "mentions": [ { "id": "384390069412429834", "name": "polyfractal", "discriminator": "0000", "nickname": "BreakingTaps", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/8d8c1d8b8ad51d6cdb1a47512c39b297-42908.png" } ], "reference": { "messageId": "1513203614556885073", "channelId": "1409664140196188251", "guildId": "1361349522684510449" }, "inlineEmojis": [] }, { "id": "1513277546849112236", "type": "Default", "timestamp": "2026-06-07T20:24:42.506+00:00", "timestampEdited": null, "callEndedTimestamp": null, "isPinned": false, "content": "So I assume you can safely ignore at 5V or 3v3", "author": { "id": "691780627338625077", "name": "rebelmike", "discriminator": "0000", "nickname": "RebelMike", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/49aaff687e56f04e7bbdedf0077bab75-7DDB4.png" }, "attachments": [], "embeds": [], "stickers": [], "reactions": [], "mentions": [], "inlineEmojis": [] }, { "id": "1513281229947142306", "type": "Default", "timestamp": "2026-06-07T20:39:20.625+00:00", "timestampEdited": null, "callEndedTimestamp": null, "isPinned": false, "content": "aha good catch! Didnt realize the docs had those tables for the sram \uD83D\uDC4D", "author": { "id": "384390069412429834", "name": "polyfractal", "discriminator": "0000", "nickname": "BreakingTaps", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/8d8c1d8b8ad51d6cdb1a47512c39b297-42908.png" }, "attachments": [], "embeds": [], "stickers": [], "reactions": [], "mentions": [], "inlineEmojis": [ { "id": "", "name": "\uD83D\uDC4D", "code": "thumbsup", "isAnimated": false, "imageUrl": "2026-06_media/1f44d-27259.svg" } ] }, { "id": "1513281248078856233", "type": "Default", "timestamp": "2026-06-07T20:39:24.948+00:00", "timestampEdited": null, "callEndedTimestamp": null, "isPinned": false, "content": "thanks!", "author": { "id": "384390069412429834", "name": "polyfractal", "discriminator": "0000", "nickname": "BreakingTaps", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/8d8c1d8b8ad51d6cdb1a47512c39b297-42908.png" }, "attachments": [], "embeds": [], "stickers": [], "reactions": [], "mentions": [], "inlineEmojis": [] }, { "id": "1513300372469448744", "type": "Default", "timestamp": "2026-06-07T21:55:24.558+00:00", "timestampEdited": null, "callEndedTimestamp": null, "isPinned": false, "content": "Does anyone have t_FO4 on hand by chance?", "author": { "id": "262706220073222144", "name": "namibj", "discriminator": "0000", "nickname": "namibj", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/f885abc0dddd0a33e4d4991b3c99091d-7ACD2.png" }, "attachments": [], "embeds": [], "stickers": [], "reactions": [], "mentions": [], "inlineEmojis": [] }, { "id": "1514906558050472026", "type": "Default", "timestamp": "2026-06-12T08:17:49.042+00:00", "timestampEdited": null, "callEndedTimestamp": null, "isPinned": false, "content": "@RebelMike @Leo Moser (mole99) Overdue update to my SCL: non-inverting latches. So you can use those now and drop any inverters you had to place in your design.\nAlways remember to gate-level simulate, there should be no more missing cell models now.", "author": { "id": "220639106915368960", "name": "tholin", "discriminator": "0000", "nickname": "Tholin", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/edae5aadf146133e0448bfb1f0fa91c4-62B19.png" }, "attachments": [], "embeds": [], "stickers": [], "reactions": [ { "emoji": { "id": "", "name": "\uD83C\uDF89", "code": "tada", "isAnimated": false, "imageUrl": "2026-06_media/1f389-5C738.svg" }, "count": 2, "users": [ { "id": "323371864074485771", "name": "mole99", "discriminator": "0000", "nickname": "Leo Moser (mole99)", "color": null, "isBot": false, "avatarUrl": "2026-06_media/3c7c17f3225f6e56f4dccd83f14383f2-73F83.png" }, { "id": "543162393413287956", "name": "h.tamas", "discriminator": "0000", "nickname": "htamas", "color": null, "isBot": false, "avatarUrl": "2026-06_media/1-B2132.png" } ] } ], "mentions": [ { "id": "323371864074485771", "name": "mole99", "discriminator": "0000", "nickname": "Leo Moser (mole99)", "color": null, "isBot": false, "roles": [ { "id": "1423020172595298314", "name": "Mod", "color": null, "position": 4 } ], "avatarUrl": "2026-06_media/3c7c17f3225f6e56f4dccd83f14383f2-73F83.png" }, { "id": "691780627338625077", "name": "rebelmike", "discriminator": "0000", "nickname": "RebelMike", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/49aaff687e56f04e7bbdedf0077bab75-7DDB4.png" } ], "inlineEmojis": [] }, { "id": "1514907040168939620", "type": "Reply", "timestamp": "2026-06-12T08:19:43.988+00:00", "timestampEdited": null, "callEndedTimestamp": null, "isPinned": false, "content": "Awesome, thank you!", "author": { "id": "691780627338625077", "name": "rebelmike", "discriminator": "0000", "nickname": "RebelMike", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/49aaff687e56f04e7bbdedf0077bab75-7DDB4.png" }, "attachments": [], "embeds": [], "stickers": [], "reactions": [], "mentions": [ { "id": "220639106915368960", "name": "tholin", "discriminator": "0000", "nickname": "Tholin", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/edae5aadf146133e0448bfb1f0fa91c4-62B19.png" } ], "reference": { "messageId": "1514906558050472026", "channelId": "1409664140196188251", "guildId": "1361349522684510449" }, "inlineEmojis": [] }, { "id": "1514912033764544625", "type": "Reply", "timestamp": "2026-06-12T08:39:34.554+00:00", "timestampEdited": null, "callEndedTimestamp": null, "isPinned": false, "content": "Opened an open_pdks PR to update the hash: https://github.com/RTimothyEdwards/open_pdks/pull/525", "author": { "id": "323371864074485771", "name": "mole99", "discriminator": "0000", "nickname": "Leo Moser (mole99)", "color": null, "isBot": false, "roles": [ { "id": "1423020172595298314", "name": "Mod", "color": null, "position": 4 } ], "avatarUrl": "2026-06_media/3c7c17f3225f6e56f4dccd83f14383f2-73F83.png" }, "attachments": [], "embeds": [], "stickers": [], "reactions": [], "mentions": [ { "id": "220639106915368960", "name": "tholin", "discriminator": "0000", "nickname": "Tholin", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/edae5aadf146133e0448bfb1f0fa91c4-62B19.png" } ], "reference": { "messageId": "1514906558050472026", "channelId": "1409664140196188251", "guildId": "1361349522684510449" }, "inlineEmojis": [] }, { "id": "1516825766879428760", "type": "Default", "timestamp": "2026-06-17T15:24:04.084+00:00", "timestampEdited": "2026-06-17T15:28:07.681+00:00", "callEndedTimestamp": null, "isPinned": false, "content": "Hello everyone I am trying to tapeout bunnie's Andrew Huang BIO Core https://www.crowdsupply.com/baochip/dabao/updates/bio-the-bao-i-o-co-processor in ws 2 run \nIt has 2 core in a half height slot, I started with 2Kb sram each core ( 4Kb total ie 8 macros of (512*8 ) ) but that arrangement is producing a lot of routing congestion \nI =have tried to stagger the columns vertically so they don't overlap in Y:\nColumn 1 (core 0): X = 442, Y = 500, 1020, 1540, 2060 (bottom half)\nColumn 2 (core 1): X = 1060, Y = 2600, 3120, 3640, 4160 (top half)\nBut that is giving bad timing paths and congestion. \n\nOnly Thing I can think of currently is to move 1Kb sram each core and use ( 8 macros of (256*8)) \n\nthis is my first time working in backend and SRAM so I would like to know is there possibility to actually fit 4Kb in the slot ? \n\nSorry if the question is dumb or confusing .", "author": { "id": "797470890765582377", "name": "deempak", "discriminator": "0000", "nickname": "Deepak", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/47fee54537e3ffc4bdae3b8edfdee6d6-DB2C1.png" }, "attachments": [ { "id": "1516825767303057519", "url": "2026-06_media/Screenshot_from_2026-06-17_18-59-23-91F74.png", "fileName": "Screenshot_from_2026-06-17_18-59-23.png", "fileSizeBytes": 319850 }, { "id": "1516825767890387074", "url": "2026-06_media/Screenshot_from_2026-06-17_19-31-18-07754.png", "fileName": "Screenshot_from_2026-06-17_19-31-18.png", "fileSizeBytes": 657346 }, { "id": "1516825768712208436", "url": "2026-06_media/Screenshot_from_2026-06-17_19-31-01-F3E17.png", "fileName": "Screenshot_from_2026-06-17_19-31-01.png", "fileSizeBytes": 883781 }, { "id": "1516825769660125275", "url": "2026-06_media/Screenshot_from_2026-06-17_19-12-42-E298B.png", "fileName": "Screenshot_from_2026-06-17_19-12-42.png", "fileSizeBytes": 796455 } ], "embeds": [ { "title": "BIO - The Bao I/O Co-Processor", "url": "https://www.crowdsupply.com/baochip/dabao/updates/bio-the-bao-i-o-co-processor", "timestamp": null, "description": "BIO is the I/O co-processor in the Baochip-1x. In this update, I’ll talk about the origins of the BIO, starting by working through a detailed study of the Raspberry Pi PIO as a reference before diving into the architecture of the BIO.", "thumbnail": { "url": "2026-06_media/5148f773-7784-4467-bcb9-bddecab01155_open--C06B1.jpg", "width": 820, "height": 1500 }, "images": [], "fields": [], "inlineEmojis": [] } ], "stickers": [], "reactions": [ { "emoji": { "id": "", "name": "\uD83D\uDC9C", "code": "purple_heart", "isAnimated": false, "imageUrl": "2026-06_media/1f49c-71A75.svg" }, "count": 1, "users": [ { "id": "756011607603019777", "name": "anfroholic", "discriminator": "0000", "nickname": "anfroholic", "color": null, "isBot": false, "avatarUrl": "2026-06_media/67bd670a335a2f955fb2ded57088a2cb-675B3.png" } ] } ], "mentions": [], "inlineEmojis": [] }, { "id": "1516842914339225756", "type": "ThreadCreated", "timestamp": "2026-06-17T16:32:12.357+00:00", "timestampEdited": null, "callEndedTimestamp": null, "isPinned": false, "content": "Started a thread.", "author": { "id": "384390069412429834", "name": "polyfractal", "discriminator": "0000", "nickname": "BreakingTaps", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/8d8c1d8b8ad51d6cdb1a47512c39b297-42908.png" }, "attachments": [], "embeds": [], "stickers": [], "reactions": [], "mentions": [], "reference": { "messageId": null, "channelId": "1516825766879428760", "guildId": "1361349522684510449" }, "inlineEmojis": [] }, { "id": "1518698602955014387", "type": "Default", "timestamp": "2026-06-22T19:26:03+00:00", "timestampEdited": null, "callEndedTimestamp": null, "isPinned": false, "content": "Here we go again!", "author": { "id": "220639106915368960", "name": "tholin", "discriminator": "0000", "nickname": "Tholin", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/edae5aadf146133e0448bfb1f0fa91c4-62B19.png" }, "attachments": [ { "id": "1518698602640314668", "url": "2026-06_media/image-D6744.png", "fileName": "image.png", "fileSizeBytes": 12392 } ], "embeds": [], "stickers": [], "reactions": [], "mentions": [], "inlineEmojis": [] }, { "id": "1518698693619089538", "type": "Default", "timestamp": "2026-06-22T19:26:24.616+00:00", "timestampEdited": null, "callEndedTimestamp": null, "isPinned": false, "content": "A bit of a problem with the 3.3V SCL: the antenna rules are even stricter for 3.3V!", "author": { "id": "220639106915368960", "name": "tholin", "discriminator": "0000", "nickname": "Tholin", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/edae5aadf146133e0448bfb1f0fa91c4-62B19.png" }, "attachments": [], "embeds": [], "stickers": [], "reactions": [], "mentions": [], "inlineEmojis": [] }, { "id": "1518720923652587540", "type": "Default", "timestamp": "2026-06-22T20:54:44.669+00:00", "timestampEdited": "2026-06-22T20:54:59.941+00:00", "callEndedTimestamp": null, "isPinned": false, "content": "huh interesting, my design is using your 3v3 library and I don't think it ran into any non-user-error antenna violations (I had a few originally because it was trying to cram logic between two closely spaced macros and then no room for diode placement). will double check when I get home, maybe it did and I didn't notice!", "author": { "id": "384390069412429834", "name": "polyfractal", "discriminator": "0000", "nickname": "BreakingTaps", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/8d8c1d8b8ad51d6cdb1a47512c39b297-42908.png" }, "attachments": [], "embeds": [], "stickers": [], "reactions": [], "mentions": [], "inlineEmojis": [] }, { "id": "1519011198845325382", "type": "Default", "timestamp": "2026-06-23T16:08:11.668+00:00", "timestampEdited": null, "callEndedTimestamp": null, "isPinned": false, "content": "https://cdn.discordapp.com/attachments/1361349523724570941/1518378503844663426/image.png?ex=6a3b052d&is=6a39b3ad&hm=0df703c1937246f2e5942d86e151188c0cc1c83dbc5a0da0886e9094c110a1db", "author": { "id": "220639106915368960", "name": "tholin", "discriminator": "0000", "nickname": "Tholin", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/edae5aadf146133e0448bfb1f0fa91c4-62B19.png" }, "attachments": [], "embeds": [ { "title": "", "url": "https://cdn.discordapp.com/attachments/1361349523724570941/1518378503844663426/image.png?ex=6a3b052d&is=6a39b3ad&hm=0df703c1937246f2e5942d86e151188c0cc1c83dbc5a0da0886e9094c110a1db", "timestamp": null, "description": "", "thumbnail": { "url": "2026-06_media/image-AB6E2.png", "width": 760, "height": 115 }, "images": [], "fields": [], "inlineEmojis": [] } ], "stickers": [], "reactions": [], "mentions": [], "inlineEmojis": [] }, { "id": "1519011218097180842", "type": "Default", "timestamp": "2026-06-23T16:08:16.258+00:00", "timestampEdited": null, "callEndedTimestamp": null, "isPinned": false, "content": "Where do I report this?", "author": { "id": "220639106915368960", "name": "tholin", "discriminator": "0000", "nickname": "Tholin", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/edae5aadf146133e0448bfb1f0fa91c4-62B19.png" }, "attachments": [], "embeds": [], "stickers": [], "reactions": [], "mentions": [], "inlineEmojis": [] }, { "id": "1519011318819196979", "type": "Default", "timestamp": "2026-06-23T16:08:40.272+00:00", "timestampEdited": "2026-06-23T16:08:50.143+00:00", "callEndedTimestamp": null, "isPinned": false, "content": "Its a major issue because the only workaround for it I’ve found so far is it to crank the area of the macro up to way above what is actually necessary", "author": { "id": "220639106915368960", "name": "tholin", "discriminator": "0000", "nickname": "Tholin", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/edae5aadf146133e0448bfb1f0fa91c4-62B19.png" }, "attachments": [], "embeds": [], "stickers": [], "reactions": [], "mentions": [], "inlineEmojis": [] }, { "id": "1519011477753823272", "type": "Default", "timestamp": "2026-06-23T16:09:18.165+00:00", "timestampEdited": null, "callEndedTimestamp": null, "isPinned": false, "content": "Which is currently having the result that using my SCL yields a *decrease* in density", "author": { "id": "220639106915368960", "name": "tholin", "discriminator": "0000", "nickname": "Tholin", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/edae5aadf146133e0448bfb1f0fa91c4-62B19.png" }, "attachments": [], "embeds": [], "stickers": [], "reactions": [], "mentions": [], "inlineEmojis": [] }, { "id": "1519011527745863831", "type": "Default", "timestamp": "2026-06-23T16:09:30.084+00:00", "timestampEdited": null, "callEndedTimestamp": null, "isPinned": false, "content": "Just by having to insert lots of blank space to stop this error from happening", "author": { "id": "220639106915368960", "name": "tholin", "discriminator": "0000", "nickname": "Tholin", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/edae5aadf146133e0448bfb1f0fa91c4-62B19.png" }, "attachments": [], "embeds": [], "stickers": [], "reactions": [], "mentions": [], "inlineEmojis": [] }, { "id": "1519012848083406930", "type": "Default", "timestamp": "2026-06-23T16:14:44.877+00:00", "timestampEdited": null, "callEndedTimestamp": null, "isPinned": false, "content": "@Tholin You're likely hitting this bug in OpenROAD: https://github.com/The-OpenROAD-Project/OpenROAD/issues/10273", "author": { "id": "323371864074485771", "name": "mole99", "discriminator": "0000", "nickname": "Leo Moser (mole99)", "color": null, "isBot": false, "roles": [ { "id": "1423020172595298314", "name": "Mod", "color": null, "position": 4 } ], "avatarUrl": "2026-06_media/3c7c17f3225f6e56f4dccd83f14383f2-73F83.png" }, "attachments": [], "embeds": [ { "title": "Underflow error after antenna repair · Issue #10273 · The-OpenROA...", "url": "https://github.com/The-OpenROAD-Project/OpenROAD/issues/10273", "timestamp": null, "description": "Describe the bug I'm getting a [ERROR GRT-0183] Net 22574: heap underflow during 3D maze routing. After antenna repair Expected Behavior No error. Environment 26Q2-555-gd71446d6e9 OpenROAD 26Q2...", "color": "#1E2327", "thumbnail": { "url": "2026-06_media/10273-0262F", "width": 1200, "height": 600 }, "images": [], "fields": [], "inlineEmojis": [] } ], "stickers": [], "reactions": [], "mentions": [ { "id": "220639106915368960", "name": "tholin", "discriminator": "0000", "nickname": "Tholin", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/edae5aadf146133e0448bfb1f0fa91c4-62B19.png" } ], "inlineEmojis": [] }, { "id": "1519013139427889182", "type": "Default", "timestamp": "2026-06-23T16:15:54.339+00:00", "timestampEdited": null, "callEndedTimestamp": null, "isPinned": false, "content": "A workaround in LibreLane is to set `CTS_APPLY_NDR: \"none\"`. It disables non-default rules for CTS.", "author": { "id": "323371864074485771", "name": "mole99", "discriminator": "0000", "nickname": "Leo Moser (mole99)", "color": null, "isBot": false, "roles": [ { "id": "1423020172595298314", "name": "Mod", "color": null, "position": 4 } ], "avatarUrl": "2026-06_media/3c7c17f3225f6e56f4dccd83f14383f2-73F83.png" }, "attachments": [], "embeds": [], "stickers": [], "reactions": [], "mentions": [], "inlineEmojis": [] }, { "id": "1519069123353513984", "type": "Reply", "timestamp": "2026-06-23T19:58:21.947+00:00", "timestampEdited": "2026-06-23T19:58:56.94+00:00", "callEndedTimestamp": null, "isPinned": false, "content": "So I tried to figure a few thing out and it looks like \nrepair_design is inserting ~12K buffers on clock nets before CTS ie +28% area explosion\nin Stage 31 (OpenROAD.RepairDesignPostGPL) inserts 12K buffers causing a +28.5% area jump. \nI then verifed in the openroad with the ODB , that shows only two nets with fanout above 50: clk_PAD2CORE (2,320 loads) and core_clk (980 loads) both are clock nets. The repair is happening entirely on clock nets that CTS then rebuilds anyway. Zero data path violations exist . What is the correct LibreLane config variable to prevent repair_design from touching clock nets before CTS runs?\n\nAlso I noticed this warning [01:21:22] WARNING [GRT-0281] Net clk_PAD2CORE has a large fanout of 2320 terminals.", "author": { "id": "797470890765582377", "name": "deempak", "discriminator": "0000", "nickname": "Deepak", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/47fee54537e3ffc4bdae3b8edfdee6d6-DB2C1.png" }, "attachments": [], "embeds": [], "stickers": [], "reactions": [], "mentions": [], "reference": { "messageId": "1516825766879428760", "channelId": "1409664140196188251", "guildId": "1361349522684510449" }, "inlineEmojis": [] }, { "id": "1519076867053719704", "type": "Reply", "timestamp": "2026-06-23T20:29:08.189+00:00", "timestampEdited": null, "callEndedTimestamp": null, "isPinned": false, "content": "Have you updated your project template and cloned the latest PDK? There was an issue in the OCD I/O cells that lead to CTS being skipped.", "author": { "id": "323371864074485771", "name": "mole99", "discriminator": "0000", "nickname": "Leo Moser (mole99)", "color": null, "isBot": false, "roles": [ { "id": "1423020172595298314", "name": "Mod", "color": null, "position": 4 } ], "avatarUrl": "2026-06_media/3c7c17f3225f6e56f4dccd83f14383f2-73F83.png" }, "attachments": [], "embeds": [], "stickers": [], "reactions": [], "mentions": [ { "id": "797470890765582377", "name": "deempak", "discriminator": "0000", "nickname": "Deepak", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/47fee54537e3ffc4bdae3b8edfdee6d6-DB2C1.png" } ], "reference": { "messageId": "1519069123353513984", "channelId": "1409664140196188251", "guildId": "1361349522684510449" }, "inlineEmojis": [] }, { "id": "1519079543699406972", "type": "Reply", "timestamp": "2026-06-23T20:39:46.351+00:00", "timestampEdited": null, "callEndedTimestamp": null, "isPinned": false, "content": "hello Yes i am on version 1.5.4 of template and i did run clone-pdk so its up to date. \n\nActually i am using a ICG Cell in my design so the clk_PAD2Core is input to that and core_clk is out put . So I suspect that .", "author": { "id": "797470890765582377", "name": "deempak", "discriminator": "0000", "nickname": "Deepak", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/47fee54537e3ffc4bdae3b8edfdee6d6-DB2C1.png" }, "attachments": [], "embeds": [], "stickers": [], "reactions": [], "mentions": [ { "id": "323371864074485771", "name": "mole99", "discriminator": "0000", "nickname": "Leo Moser (mole99)", "color": null, "isBot": false, "roles": [ { "id": "1423020172595298314", "name": "Mod", "color": null, "position": 4 } ], "avatarUrl": "2026-06_media/3c7c17f3225f6e56f4dccd83f14383f2-73F83.png" } ], "reference": { "messageId": "1519076867053719704", "channelId": "1409664140196188251", "guildId": "1361349522684510449" }, "inlineEmojis": [] }, { "id": "1519080970324807864", "type": "Default", "timestamp": "2026-06-23T20:45:26.485+00:00", "timestampEdited": null, "callEndedTimestamp": null, "isPinned": false, "content": "It's possible that adding them to CLOCK_NET in the config would help. I have: ```\nCLOCK_NET:\n- i_chip_core.real_clk_gf180mcu_as_sc_mcu7t3v3__mux2_2_Y/Y\n- clk5x_pad/Y\n```", "author": { "id": "691780627338625077", "name": "rebelmike", "discriminator": "0000", "nickname": "RebelMike", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/49aaff687e56f04e7bbdedf0077bab75-7DDB4.png" }, "attachments": [], "embeds": [], "stickers": [], "reactions": [], "mentions": [], "inlineEmojis": [] }, { "id": "1519179629078909128", "type": "Reply", "timestamp": "2026-06-24T03:17:28.565+00:00", "timestampEdited": "2026-06-24T03:17:50.275+00:00", "callEndedTimestamp": null, "isPinned": false, "content": "Hello thank you , the sdc should add these clock nets as create clock right ? or clock group", "author": { "id": "797470890765582377", "name": "deempak", "discriminator": "0000", "nickname": "Deepak", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/47fee54537e3ffc4bdae3b8edfdee6d6-DB2C1.png" }, "attachments": [], "embeds": [], "stickers": [], "reactions": [], "mentions": [ { "id": "691780627338625077", "name": "rebelmike", "discriminator": "0000", "nickname": "RebelMike", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/49aaff687e56f04e7bbdedf0077bab75-7DDB4.png" } ], "reference": { "messageId": "1519080970324807864", "channelId": "1409664140196188251", "guildId": "1361349522684510449" }, "inlineEmojis": [] }, { "id": "1519234163645878302", "type": "Default", "timestamp": "2026-06-24T06:54:10.619+00:00", "timestampEdited": null, "callEndedTimestamp": null, "isPinned": false, "content": "So the congestion seems to be only get blobbed in a small section of the chip rest is just empty and tht is creating overflow in that local congestion And that ends up begin overflow in the GRT ( or that what i understood atleast)\n\n\nIs there a way to spread it I have tried with different logic density already form 30 to 50 \nAnd sorry fro continues spam here i am bit newbie in Pnr .", "author": { "id": "797470890765582377", "name": "deempak", "discriminator": "0000", "nickname": "Deepak", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/47fee54537e3ffc4bdae3b8edfdee6d6-DB2C1.png" }, "attachments": [ { "id": "1519234163331436544", "url": "2026-06_media/Screenshot_from_2026-06-24_11-54-53-B69D3.png", "fileName": "Screenshot_from_2026-06-24_11-54-53.png", "fileSizeBytes": 637491 } ], "embeds": [], "stickers": [], "reactions": [], "mentions": [], "inlineEmojis": [] }, { "id": "1519237258702749877", "type": "Reply", "timestamp": "2026-06-24T07:06:28.538+00:00", "timestampEdited": null, "callEndedTimestamp": null, "isPinned": false, "content": "The variable you are searching for is [PL_TARGET_DENSITY_PCT](https://github.com/wafer-space/gf180mcu-project-template/blob/1db3a3bf89491ed497e21208e82f95734bab98db/librelane/config.yaml#L75). Note that a lower value means a higher spread.\n\nWhat kind of message do you get during GRT? Normally, you can always continue at least to DRT if `GRT_ALLOW_CONGESTION: true`.", "author": { "id": "323371864074485771", "name": "mole99", "discriminator": "0000", "nickname": "Leo Moser (mole99)", "color": null, "isBot": false, "roles": [ { "id": "1423020172595298314", "name": "Mod", "color": null, "position": 4 } ], "avatarUrl": "2026-06_media/3c7c17f3225f6e56f4dccd83f14383f2-73F83.png" }, "attachments": [], "embeds": [], "stickers": [], "reactions": [], "mentions": [ { "id": "797470890765582377", "name": "deempak", "discriminator": "0000", "nickname": "Deepak", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/47fee54537e3ffc4bdae3b8edfdee6d6-DB2C1.png" } ], "reference": { "messageId": "1519234163645878302", "channelId": "1409664140196188251", "guildId": "1361349522684510449" }, "inlineEmojis": [] }, { "id": "1519239408069513297", "type": "Reply", "timestamp": "2026-06-24T07:15:00.987+00:00", "timestampEdited": "2026-06-24T07:17:31.343+00:00", "callEndedTimestamp": null, "isPinned": false, "content": "Yes I have iterated PL_TARGET_DENSITY_PCT from 30 to 50 but the results were creating same number of overflows ie is around 18 K \nThe flow does go to the Detailed routing as i have kept GRT_ALLOW_CONGESTION: true but DRT starts with 90K violations and then just keeps on iterating it did went down to 79K but that took 12h . \nThen my system killed the process but I think 12h was too much anyway? Or is that normal \n\n\nI search on internet and found that maybe adding PAD_CELL might help what is you take on that ?", "author": { "id": "797470890765582377", "name": "deempak", "discriminator": "0000", "nickname": "Deepak", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/47fee54537e3ffc4bdae3b8edfdee6d6-DB2C1.png" }, "attachments": [], "embeds": [], "stickers": [], "reactions": [], "mentions": [ { "id": "323371864074485771", "name": "mole99", "discriminator": "0000", "nickname": "Leo Moser (mole99)", "color": null, "isBot": false, "roles": [ { "id": "1423020172595298314", "name": "Mod", "color": null, "position": 4 } ], "avatarUrl": "2026-06_media/3c7c17f3225f6e56f4dccd83f14383f2-73F83.png" } ], "reference": { "messageId": "1519237258702749877", "channelId": "1409664140196188251", "guildId": "1361349522684510449" }, "inlineEmojis": [] }, { "id": "1519240447656984697", "type": "Reply", "timestamp": "2026-06-24T07:19:08.844+00:00", "timestampEdited": null, "callEndedTimestamp": null, "isPinned": false, "content": "You need to lower the value to spread the cells. For example. try `PL_TARGET_DENSITY_PCT: 20`.", "author": { "id": "323371864074485771", "name": "mole99", "discriminator": "0000", "nickname": "Leo Moser (mole99)", "color": null, "isBot": false, "roles": [ { "id": "1423020172595298314", "name": "Mod", "color": null, "position": 4 } ], "avatarUrl": "2026-06_media/3c7c17f3225f6e56f4dccd83f14383f2-73F83.png" }, "attachments": [], "embeds": [], "stickers": [], "reactions": [], "mentions": [ { "id": "797470890765582377", "name": "deempak", "discriminator": "0000", "nickname": "Deepak", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/47fee54537e3ffc4bdae3b8edfdee6d6-DB2C1.png" } ], "reference": { "messageId": "1519239408069513297", "channelId": "1409664140196188251", "guildId": "1361349522684510449" }, "inlineEmojis": [] }, { "id": "1519241265584148491", "type": "Reply", "timestamp": "2026-06-24T07:22:23.853+00:00", "timestampEdited": null, "callEndedTimestamp": null, "isPinned": false, "content": "my design utilisation was 27 % so i thought i should keep above that if that's not the case i will try 20 now \nThank You much", "author": { "id": "797470890765582377", "name": "deempak", "discriminator": "0000", "nickname": "Deepak", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/47fee54537e3ffc4bdae3b8edfdee6d6-DB2C1.png" }, "attachments": [], "embeds": [], "stickers": [], "reactions": [], "mentions": [ { "id": "323371864074485771", "name": "mole99", "discriminator": "0000", "nickname": "Leo Moser (mole99)", "color": null, "isBot": false, "roles": [ { "id": "1423020172595298314", "name": "Mod", "color": null, "position": 4 } ], "avatarUrl": "2026-06_media/3c7c17f3225f6e56f4dccd83f14383f2-73F83.png" } ], "reference": { "messageId": "1519240447656984697", "channelId": "1409664140196188251", "guildId": "1361349522684510449" }, "inlineEmojis": [] }, { "id": "1519241618325115022", "type": "Reply", "timestamp": "2026-06-24T07:23:47.953+00:00", "timestampEdited": null, "callEndedTimestamp": null, "isPinned": false, "content": "Increasing the target density means a higher routing congestion. Good luck!", "author": { "id": "323371864074485771", "name": "mole99", "discriminator": "0000", "nickname": "Leo Moser (mole99)", "color": null, "isBot": false, "roles": [ { "id": "1423020172595298314", "name": "Mod", "color": null, "position": 4 } ], "avatarUrl": "2026-06_media/3c7c17f3225f6e56f4dccd83f14383f2-73F83.png" }, "attachments": [], "embeds": [], "stickers": [], "reactions": [ { "emoji": { "id": "", "name": "❤️", "code": "heart", "isAnimated": false, "imageUrl": "2026-06_media/2764-A3D25.svg" }, "count": 1, "users": [ { "id": "797470890765582377", "name": "deempak", "discriminator": "0000", "nickname": "Deepak", "color": null, "isBot": false, "avatarUrl": "2026-06_media/47fee54537e3ffc4bdae3b8edfdee6d6-DB2C1.png" } ] } ], "mentions": [ { "id": "797470890765582377", "name": "deempak", "discriminator": "0000", "nickname": "Deepak", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/47fee54537e3ffc4bdae3b8edfdee6d6-DB2C1.png" } ], "reference": { "messageId": "1519241265584148491", "channelId": "1409664140196188251", "guildId": "1361349522684510449" }, "inlineEmojis": [] }, { "id": "1519280217909366815", "type": "Reply", "timestamp": "2026-06-24T09:57:10.811+00:00", "timestampEdited": null, "callEndedTimestamp": null, "isPinned": false, "content": "this worked thank you very much", "author": { "id": "797470890765582377", "name": "deempak", "discriminator": "0000", "nickname": "Deepak", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/47fee54537e3ffc4bdae3b8edfdee6d6-DB2C1.png" }, "attachments": [], "embeds": [], "stickers": [], "reactions": [], "mentions": [ { "id": "323371864074485771", "name": "mole99", "discriminator": "0000", "nickname": "Leo Moser (mole99)", "color": null, "isBot": false, "roles": [ { "id": "1423020172595298314", "name": "Mod", "color": null, "position": 4 } ], "avatarUrl": "2026-06_media/3c7c17f3225f6e56f4dccd83f14383f2-73F83.png" } ], "reference": { "messageId": "1519241618325115022", "channelId": "1409664140196188251", "guildId": "1361349522684510449" }, "inlineEmojis": [] }, { "id": "1519280404090064917", "type": "Reply", "timestamp": "2026-06-24T09:57:55.2+00:00", "timestampEdited": null, "callEndedTimestamp": null, "isPinned": false, "content": "That's great to hear!", "author": { "id": "323371864074485771", "name": "mole99", "discriminator": "0000", "nickname": "Leo Moser (mole99)", "color": null, "isBot": false, "roles": [ { "id": "1423020172595298314", "name": "Mod", "color": null, "position": 4 } ], "avatarUrl": "2026-06_media/3c7c17f3225f6e56f4dccd83f14383f2-73F83.png" }, "attachments": [], "embeds": [], "stickers": [], "reactions": [], "mentions": [ { "id": "797470890765582377", "name": "deempak", "discriminator": "0000", "nickname": "Deepak", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/47fee54537e3ffc4bdae3b8edfdee6d6-DB2C1.png" } ], "reference": { "messageId": "1519280217909366815", "channelId": "1409664140196188251", "guildId": "1361349522684510449" }, "inlineEmojis": [] }, { "id": "1519722886246694912", "type": "Default", "timestamp": "2026-06-25T15:16:11.167+00:00", "timestampEdited": null, "callEndedTimestamp": null, "isPinned": false, "content": "Is there a better open-source tool than yosys/abc for retiming?", "author": { "id": "290925586266980352", "name": "osvel", "discriminator": "0000", "nickname": "Olle", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/0a78dc08258cf53bd8ec52dd3e14ef57-26F82.png" }, "attachments": [], "embeds": [], "stickers": [], "reactions": [], "mentions": [], "inlineEmojis": [] }, { "id": "1519723102152556695", "type": "Default", "timestamp": "2026-06-25T15:17:02.643+00:00", "timestampEdited": null, "callEndedTimestamp": null, "isPinned": false, "content": "I don't really understand it i guess, it feels like it doesn't work", "author": { "id": "290925586266980352", "name": "osvel", "discriminator": "0000", "nickname": "Olle", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/0a78dc08258cf53bd8ec52dd3e14ef57-26F82.png" }, "attachments": [], "embeds": [], "stickers": [], "reactions": [], "mentions": [], "inlineEmojis": [] }, { "id": "1521239998467407892", "type": "Reply", "timestamp": "2026-06-29T19:44:38.907+00:00", "timestampEdited": null, "callEndedTimestamp": null, "isPinned": false, "content": "what problem are you encountering?", "author": { "id": "236632873782738944", "name": ".pogeg", "discriminator": "0000", "nickname": "Jason Yang", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/e31b263653838da47e41a71360dba87e-C926B.png" }, "attachments": [], "embeds": [], "stickers": [], "reactions": [], "mentions": [ { "id": "290925586266980352", "name": "osvel", "discriminator": "0000", "nickname": "Olle", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/0a78dc08258cf53bd8ec52dd3e14ef57-26F82.png" } ], "reference": { "messageId": "1519722886246694912", "channelId": "1409664140196188251", "guildId": "1361349522684510449" }, "inlineEmojis": [] }, { "id": "1521241383191449703", "type": "Default", "timestamp": "2026-06-29T19:50:09.051+00:00", "timestampEdited": "2026-06-29T19:50:31.54+00:00", "callEndedTimestamp": null, "isPinned": false, "content": "From a software perspective, I guess I assume retiming to be more powerful than it is.\n\nI was under the impression that this should distribute the implementation (booth or whatever) over multiple cycles (i.e, balance the gates):\n```verilog\nmodule IntegerMultiply(\n input clock,\n input [31:0] inA,\n inB,\n output [31:0] out\n);\n\n reg [31:0] prod_pipe_r0;\n reg [31:0] prod_pipe_r1;\n reg [31:0] prod_pipe_r2;\n reg [31:0] prod_pipe;\n always @(posedge clock) begin\n prod_pipe_r0 <= (inA * inB);\n prod_pipe_r1 <= prod_pipe_r0;\n prod_pipe_r2 <= prod_pipe_r1;\n prod_pipe <= prod_pipe_r2;\n end\n assign out = prod_pipe;\nendmodule\n```\nThis is for an ASIC, using abc (not abc9)", "author": { "id": "290925586266980352", "name": "osvel", "discriminator": "0000", "nickname": "Olle", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/0a78dc08258cf53bd8ec52dd3e14ef57-26F82.png" }, "attachments": [], "embeds": [], "stickers": [], "reactions": [], "mentions": [], "inlineEmojis": [] }, { "id": "1521248657754685450", "type": "Default", "timestamp": "2026-06-29T20:19:03.442+00:00", "timestampEdited": null, "callEndedTimestamp": null, "isPinned": false, "content": "Is retiming even enabled by default in the flow ?", "author": { "id": "596068704471482370", "name": "246tnt", "discriminator": "0000", "nickname": "tnt", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/88d17af9d19ab43565b0c46751ef7d12-DFEE5.png" }, "attachments": [], "embeds": [], "stickers": [], "reactions": [], "mentions": [], "inlineEmojis": [] }, { "id": "1521269326542536764", "type": "Default", "timestamp": "2026-06-29T21:41:11.265+00:00", "timestampEdited": null, "callEndedTimestamp": null, "isPinned": false, "content": "I'm fairly sure retiming doesn't happen in the Librelane flow. Though interestingly `retime` is passed to ABC.\nI found this in a search: https://github.com/The-OpenROAD-Project/OpenROAD-flow-scripts/discussions/1782#discussioncomment-8264228 which suggests ABC only sees combinational logic. Which is possibly why you always see the error `ABC: Error: The network is combinational.` \nBut clearly yosys *can* do retiming because it works on some FPGA flows - I guess if you wanted to investigate further you could compare the synth scripts for an FPGA and librelane", "author": { "id": "691780627338625077", "name": "rebelmike", "discriminator": "0000", "nickname": "RebelMike", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/49aaff687e56f04e7bbdedf0077bab75-7DDB4.png" }, "attachments": [], "embeds": [], "stickers": [], "reactions": [], "mentions": [], "inlineEmojis": [] }, { "id": "1521271913056440571", "type": "Default", "timestamp": "2026-06-29T21:51:27.938+00:00", "timestampEdited": "2026-06-29T21:51:52.066+00:00", "callEndedTimestamp": null, "isPinned": false, "content": "Interesting. I'm pretty sure I got it to work at least once. I have done so many experiments so I feel a bit lost, but iirc retiming worked well until i added input/output delays in my .sbc file. I'll do some more experiments tomorrow and update.", "author": { "id": "290925586266980352", "name": "osvel", "discriminator": "0000", "nickname": "Olle", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/0a78dc08258cf53bd8ec52dd3e14ef57-26F82.png" }, "attachments": [], "embeds": [], "stickers": [], "reactions": [], "mentions": [], "inlineEmojis": [] }, { "id": "1521329070275825845", "type": "Reply", "timestamp": "2026-06-30T01:38:35.281+00:00", "timestampEdited": null, "callEndedTimestamp": null, "isPinned": false, "content": "(it doesn't work very well though, because it retimes after mapping LUTs, not during mapping LUTs)", "author": { "id": "1187141985530818611", "name": "ravenslofty", "discriminator": "0000", "nickname": "Lofty", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/dd665ae27be32531af89aeb08fd05e04-1D5A4.png" }, "attachments": [], "embeds": [], "stickers": [], "reactions": [], "mentions": [ { "id": "691780627338625077", "name": "rebelmike", "discriminator": "0000", "nickname": "RebelMike", "color": null, "isBot": false, "roles": [], "avatarUrl": "2026-06_media/49aaff687e56f04e7bbdedf0077bab75-7DDB4.png" } ], "reference": { "messageId": "1521269326542536764", "channelId": "1409664140196188251", "guildId": "1361349522684510449" }, "inlineEmojis": [] } ], "messageCount": 45 }