diff --git a/readme.md b/readme.md
index 2dcd34c..ab20fae 100644
--- a/readme.md
+++ b/readme.md
@@ -8,40 +8,40 @@
 - [ ] Consider adding a way to visualize screen memory
 - [ ] Do a proper binary version...
 
-## ISA
+## Instruction set
+
+    0   END
+    1   STO lit#   ; store ... mem[lit#] <- A
+    2   STO addr   ; store ... mem[mem[addr]] <- A
+    3   LDA lit#   ; load  ... A <- lit#
+    4   LDA addr   ; load  ... A <- mem[addr]
+    5   ADD lit#   ; add   ... A <- A + lit#      ... and un/set carry flag
+    6   ADD addr   ; add   ... A <- A + mem[addr] ... and un/set carry flag
+    7   SUB lit#   ; sub   ... A <- A - lit#      ... and un/set carry flag
+    8   SUB addr   ; sub   ... A <- A - mem[addr] ... and un/set carry flag
+    9   HOP lit#   ; hop   ... skip next instruction if A == lit# ... when true: IP <- PC + 2
+    A   HOP addr   ; hop   ... skip next instruction if A == addr ... when true: IP <- PC + 2
+    B   JMP lit#   ; jump  ... IP <- lit#
+    C   JMP addr   ; jump  ... IP <- addr
+    D   CCF ————   ; clear Carry Flag ... CF = 0
+    E   CHP ----   ; carry hop ... skip next instruction if Carry Flag is set ... when true: IP <- PC + 2
+    F
 
-0 END
-1 STO lit# ; store ... mem[lit#] <- A
-2 STO addr ; store ... mem[mem[addr]] <- A
-3 LDA lit# ; load  ... A <- lit#
-4 LDA addr ; load  ... A <- mem[addr]
-5 ADD lit# ; add   ... A <- A + lit#     ... and un/set carry flag
-6 ADD addr ; add   ... A <- A + mem[addr] ... and un/set carry flag
-7 SUB lit# ; sub   ... A <- A - lit#     ... and un/set carry flag
-8 SUB addr ; sub   ... A <- A - mem[addr] ... and un/set carry flag
-9 HOP lit# ; skip next instruction if A == lit# ... when true: IP <- PC + 2
-A HOP addr ; skip next instruction if A == addr ... when true: IP <- PC + 2
-B JMP lit# ; ... IP <- lit#
-C JMP addr ; ... IP <- addr
-~~D CAT ---- ; Carry Flag Toggle ... CF <- !CF~~
-D CCF ———— ; Clear Carry Flag ... CF = 0
-E CHP ---- ; skip next instruction if Carry Flag is set ... when true: IP <- PC + 2
-F
 
 ### Nice features that didn't fit
 
-- hop IF< and hop IF>
-- MUL and DIV
+- hop `IF<` and hop `IF>`
+- `MUL` and `DIV`
 - rotates and shifts
 
 ## Registers
 
-- A -- accumulator
-- IP -- instruction pointer (aka program counter)
+- `A` - accumulator
+- `IP` - instruction pointer (aka program counter)
 
 ## Flags
 
-- CF -- carry flag
+- `CF` - carry flag
 
 ## Memory-mapped peripherals
 
@@ -55,7 +55,7 @@ F
 
 ## Tentative memory map
 
-00-0F - display
-10-1F - keypad? (details TBD)
-20    - initial value for IP ?
-21-FF - free
\ No newline at end of file
+    00-0F - display
+    10-1F - keypad? (details TBD)
+    20    - initial value for IP ?
+    21-FF - free
\ No newline at end of file