endbss - begbss is no longer computable by the assembler

diff --git a/mach/i80/libmon/head_em.s b/mach/i80/libmon/head_em.s
index b4b3b2d..2e28aff 100644 (file)
--- a/mach/i80/libmon/head_em.s
+++ b/mach/i80/libmon/head_em.s
@@ -12,8 +12,14 @@
 .sect .text
        lxi h,0x1000            ! stack will grow from 0x1000 downwards
        sphl
+       lxi d,endbss
        lxi h,begbss            ! clear bss
-       lxi d,endbss-begbss
+       mov a,e
+       sub l
+       mov e,a
+       mov a,d
+       sbb h
+       mov d,a                 ! de now contains endbss - begbss
        mvi c,0
 
 2:     mov m,c