diff --git a/ld/devices.data b/ld/devices.data
index 69756e98..23990d48 100644
--- a/ld/devices.data
+++ b/ld/devices.data
@@ -186,8 +186,34 @@ stm32f7[67][89]?i* stm32f7ccm ROM=2048K RAM=384K CCM=128K
 stm32f750* stm32f7ccm ROM=64K RAM=256K CCM=64K
 stm32f730* stm32f7ccm ROM=64K RAM=192K CCM=64K
 
-# on u5 the RAM1 and RAM2 can be combined to create one bigger bank
-stm32u5[78]5* stm32u5 ROM=2048K RAM=768K RAM3=512K RAM4=4K
+# STM32U5 family
+# These parts have (at this writing) up to 7 SRAM sections (1 - 7) but not
+# all parts have all SRAM. For example the smallest parts (535/545) have
+# SRAM1, SRAM2, and SRAM4 but are missing SRAM3. If you don't specify a
+# flash size (trailing E/C/B/G/I/J) you get the smallest flash for that
+# group
+#
+# RM0456, Rev 6 plus individual device data sheets.
+# 
+# STM32U535/U545 have SRAM1, 2, and 4 and 128K, 256K, and 512K of FLASH
+stm32u5[34]5*e stm32u5 ROM=512K RAM=256K SRAM4=16K SRAM4_OFFSET=0x200C0000
+stm32u5[34]5*c stm32u5 ROM=256K RAM=256K SRAM4=16K SRAM4_OFFSET=0x200C0000
+stm32u5[34]5*b stm32u5 ROM=128K RAM=256K SRAM4=16K SRAM4_OFFSET=0x200C0000
+stm32u5[34]5*  stm32u5 ROM=128K RAM=256K SRAM4=16K SRAM4_OFFSET=0x200C0000
+# STM32U575/U585 have SRAM1, SRAM2, SRAM3, SRAM4
+stm32u575*g    stm32u5 ROM=2048K RAM=768K SRAM4=16K SRAM4_OFFSET=0x200C0000
+stm32u575*i    stm32u5 ROM=1024K RAM=768K SRAM4=16K SRAM4_OFFSET=0x200C0000
+stm32u575*     stm32u5 ROM=1024K RAM=768K SRAM4=16K SRAM4_OFFSET=0x200C0000
+stm32u585*     stm32u5 ROM=2048K RAM=768K SRAM4=16K SRAM4_OFFSET=0x200C0000
+# STM32U59* have SRAM1, SRAM2, SRAM3, SRAM4, SRAM5 (SRAM 4 in the middle of
+# that, still is "special" in that it works while asleep
+stm32u59*j     stm32u5 ROM=4096K RAM=2512K
+stm32u59*i     stm32u5 ROM=2048K RAM=2512K
+stm32u59*      stm32u5 ROM=2048K RAM=2512K
+# STM32U5A* have same memories as 595 (1-5)
+stm32u5a*      stm32u5 ROM=4096K RAM=2512K
+# STM32U5F* Adds SRAM6 and U5G dual banks flash (so 8192K but only 4096K active)
+stm32u5[fg]*   stm32u5 ROM=4096K RAM=3024K
 
 stm32l01??3* stm32l0 ROM=8K RAM=2K
 stm32l0[12]??4* stm32l0 ROM=16K RAM=2K
@@ -597,7 +623,7 @@ stm32f7 END ROM_OFF=0x08000000 RAM_OFF=0x20010000 CPU=cortex-m7 FPU=hard-fpv5-sp
 stm32l0 END ROM_OFF=0x08000000 RAM_OFF=0x20000000 CPU=cortex-m0plus FPU=soft
 stm32l1 END ROM_OFF=0x08000000 RAM_OFF=0x20000000 CPU=cortex-m3 FPU=soft
 stm32l4 END ROM_OFF=0x08000000 RAM_OFF=0x20000000 RAM2_OFF=0x10000000 RAM3_OFF=0x20040000 CPU=cortex-m4 FPU=hard-fpv4-sp-d16
-stm32u5 END ROM_OFF=0x08000000 RAM_OFF=0x20000000 RAM2_OFF=0x20030000 RAM3_OFF=0x20040000 RAM4_OFF=0x28000000 CPU=cortex-m33 FPU=hard-fpv5-sp-d16
+stm32u5 END ROM_OFF=0x08000000 RAM_OFF=0x20000000 SRAM4_OFF=0x200C0000 CPU=cortex-m33 FPU=hard-fpv5-sp-d16
 stm32g0 END ROM_OFF=0x08000000 RAM_OFF=0x20000000 CPU=cortex-m0plus FPU=soft
 stm32g4 END ROM_OFF=0x08000000 RAM_OFF=0x20000000 CPU=cortex-m4 FPU=hard-fpv4-sp-d16
 stm32h7 END ROM_OFF=0x08000000 ROM2_OFF=0x08100000 RAM_OFF=0x24000000 RAM2_OFF=0x30000000 RAM3_OFF=0x30020000 RAM4_OFF=0x30040000 RAM5_OFF=0x38000000 CCM_OFF=0x20000000 CPU=cortex-m7 FPU=hard-fpv5-d16